Mark can't wait for Catherine to unlock the door he has never wanted anyone more in his life the way he wants Catherine right now. Catherine opens the door and let's Mark in, she closes and locks the door behind her. They immediately embrace into a passionate kiss falling backwards onto the couch. Marks laughs as they land and continues kissing Catherine.

After a while Catherine asks out breath, "Would you like to continue this upstairs?"

Mark gives an "Mhhmmm," during a kiss.

They get up from the couch still kissing while walking to the stairs. Half way up the stairs they fall again both laughing and Mark says, "We should probably take a break so we can actually make it to the bedroom."

Catherine takes Mark's hand and leads him to her bedroom. Once in Catherine's bedroom Mark starts kissing her again. Catherine begins taking off Mark's shirt, he notices and takes off Catherine's at the same time. Mark starts kissing Catherine's neck and shoulder. Catherine stops him for a second and sits on her bed and pulls Mark down on top of her.

Mark kisses Catherine very passionately but suddenly stops out of breath and looks into Catherine's eyes and says, "I hope you are sure about this because I've never been more sure of anything in my entire life."

Catherine instead of responding starts kissing him once again.

Sometime later …

Mark lies on his back one arm underneath Catherine with her head lying on his shoulder. This a position Mark and Catherine have grown accustom to this past week. Marks looks down at Catherine and smiles.

Catherine looks up at Mark and says, "I could lay like this forever."

Mark laughs confusing Catherine. Mark looks and sees this and he says, "Oh honey it's nothing bad it's just when you said that all of a sudden we became a Savage Garden song."

Catherine looks at him questioningly.

Mark starts signing, "I'll be your dream I'll be your wish I'll be your fantasy. I'll be your hope I'll be your love be everything that you need. I'll love you more with every breath truly madly deeply do. I will be strong I will be faithful cause I'm counting on a new beginning a reason for living a deeper meaning yeah. I want to stand with you on a mountain. I want to bathe with you in the sea. I want to lay like this forever until the sky falls down on me."

Catherine leans up and kisses Mark, "Wow I don't think anyone has ever serenaded me in bed before that is definitely a first."

Mark rolls on top of Catherine and kisses her back, "I hope to be a lot of your firsts." As they begin to make love again.

Several hours later …

Mark wakes up to his phone going off to Kerri's ringtone. He answers sleepily, "Anderson."

Kerri laughs and says, "Well don't you sound all professional even in your sleep."

Mark laughs and asks, "Hey what time is it?"

Kerri responds, "It's around 11:30 and since you didn't come home I'm assuming you got lucky. I was just checking to make sure you still weren't working."

Mark says, "Maybe I did get lucky and no I'm definitely not working. I'll see you later."

Mark hangs ups the call and turns on his side and snuggles up to Catherine as his kisses the back of her neck.

Catherine lets out a small moan and turns around to face Mark giving him a small kiss. They fall asleep again holding each other.

About 1pm Mark's phone goes off again he answers, "Anderson."

Greg says, "Hey Mark, it's Greg. The guys and I are meeting for lunch and I wanted to know if you'd like to join us?"

Mark responds, "The guys?"

Greg answers, "Yeah me, Nick, Warrick and Archie. It's something we try to do about once a month; you know get together just the guys."

Marks says, "That sounds great let me shower and get myself together. Text me the address."

Greg says, "Actually, it's the diner right down the street from the lab. Do you know where that is?"

Mark says, "Oh yeah I went there to grab lunch my first day. I'll see you soon."

Mark hangs up the phone and realizes he is alone in bed. He sits on the edge of the bed searching for his clothes. He laughs and says to himself, "I am going to have to search for my clothes every time we have sex?"

Catherine emerges from the bathroom hearing this responds, "I'd say it's a definite possibility. Nice to see you awake. Did I hear you on the phone?"

Mark responds, "Yeah Greg invited me to a guy's lunch with him, Nick, Warrick, and Archie. I guess it's something they try to do once a month and wanted to include me."

Catherine smiles and says, "Good nice to see a little male bonding going on with my team."

Mark laughs, "Oh yeah that's right you are the assistant supervisor to Grissom. Does sleeping with you help me get to the top?"

Catherine playfully slaps Mark's chest and says, "If your evaluation is based upon last night's performance your chances of advancing are good."

Mark gives her a long slow kiss and says, "You should have waited and we could have shared a shower and conserved some water."

Catherine looks at Mark and says, "Oh is that what we're going to call it now 'conserving water'? I like it. Do you want me to drop you off after you shower?"

Mark says, "I'm actually getting ready to call Kerri and see if Elizabeth can pick me up I think she's meeting Brass to tour the lab and PD today."

Catherine says, "Ok," and gets dressed.

Mark dials Kerri, "Hey what's up?"

Kerri says, "Not much I'm watching Elizabeth go through outfits like candy, she's freaking out like it's a job interview I keep telling her it's just a tour."

Mark responds, "Well I'm sure it somewhat is they know she is interested and know that people in the department can vouch for her it's really a matter of formalities after that I'm sure."

Kerri says, "I guess you're right. What are you up to?"

Mark replies, "I was wondering if Elizabeth could stop by in my Jeep and pick me up from Catherine's and drop me at a diner just down the street from the lab?"

Kerri says, "Yeah I'll have her do that is an hour good? I'll go push her along."

Mark replies, "Yeah that should be fine I'll see her soon."

Catherine looks at Mark and says, "Everything you need should be in the bathroom, let me know if you need anything."

Mark says, "Thanks," and goes into the bathroom and shuts the door.

Catherine hearing the shower start grabs her phone and dials an all too familiar number and says, "Hey Warrick."

Warrick responds, "Hey Cath what's up?"

"Not much …" says Catherine.

Warrick knows this tone all too well, him and Catherine are best friends and he knows she's contemplating something and needs advice. Warrick says, "Ok what's really up? I know that tone."

"Well, Mark and I ironically knew each other before he started at the lab," says Catherine.

"Oh really I thought something might be up. Some lab people were buzzing on how you two seem to be fast friends already," says Warrick.

"Yeah he and I hooked up the night before he started. I didn't know who he was; we met at a bar in the Bellagio where he was staying. I got called into work and left his hotel room and left him a note to call me. Next thing I know Grissom is introducing him to the group. I was on vacation with Lindsey when his interview was done," Catherine states really quickly.

Warrick blown away by all this says, "Wow that had to be a little shocking. How are you all handling it? Are you going to tell Gris?"

Catherine pauses for a second thinking; "Well, Mark came over for lunch after his first shift and we decided that taking it slow was the best thing to do since there was more on the line now with us both working at the lab; and that if we decided this thing is serious then we would tell Grissom, no reason jumping the gun. We went on an official first date on Tuesday night and he was a complete gentlemen and we had a great time, we get along so well. Wednesday I helped him move into his apartment. I called Greg because I knew he had the day off to help. Mark had his two friends, Kerri and Elizabeth, they drove a U-Haul of his stuff from Ohio. They are two of the sweetest people you could ever meet and they just adore Mark. I stayed at his apartment that night and nothing happened we cuddled and talked most of the night. I worked part of the night Thursday that he had off and I went over when I got off and again nothing happened we just cuddled. We went into work together yesterday and came back to my house to be alone since his friends are staying in his apartment and Warrick I'm not sure sex with anyone has ever been like that … I think I know what people mean by making love now."

Warrick replies, "Cath I'm really happy for you. Have you told Mark how you feel about last night yet? Honestly that sounds like you love him."

Catherine shakes her head and replies, "No, but this thing has quickly taken a serious turn. I need to talk to him and see if he thinks we should go to Grissom. Oh apparently he's having lunch with you, Greg, Nick and Archie in a few."

Warrick responds, "Yeah I heard, it should be fun. By the way I know what you're asking without saying it, I will look out for Mark. Anyone you know and love is someone that I also love and care about."

Catherine smiles knowing that she called the right person and asks, "What would I do without you?"

Warrick replies, "I'm sure you'd do just fine. I'll see you at work."

Catherine says, "Bye," and hangs up the phone. Suddenly everything seemed ok but she still needed to talk to Mark and possibly Gil. The hard part hadn't even started.