You and Temmie walked back to Undyne's house to find Sans standing in front of the door ,waiting for you two to return. He sees you then grins and waves "Hey ! You want to hang out again?..."
You smiled happily "Sure!"
While you and Sans were walking through the caverns, you came upon an telescope then walked up to it. Sans sees it then grins mischievously "You want to take a look?" You looked in the telescope, but couldn't see anything, all you could see was red. You pulled your head back and looked at Sans disappointed "Sans I can't see any-" You stopped when you see him snickering at you.
You raised an eyebrow in confusion "What's so funny?"
He kneels over clenching his chest, laughing out loud "*Phfft! Ha Ha Ha!"
You put your hands on your hips, getting a little agitated "I don't get it...What's so funny?"
He tries to catch his breath then stands up and hands you an mirror "Check out your shiner!"
You took the mirror and you see that your eye was covered with red paint. Embarrassed, you quickly wiped off the paint then you smiled a little irked at what happened then answered sarcastically "Oh, Ha, Ha, very funny." He looks away then shrugs innocently "Come on... you practically walked right into that."
Then you smiled deviously when you came up with an idea to get him back "Hey Sans..." He looks at you nervously thinking that you were still mad at him "W-what?..." You smiled and said "Updog!" He looks at you confused "What?" "You know updog!" He answered confused "What is up dog?" You started to snicker when he finished saying it, then he realized what he had said, and started laughing along with you.
Afterwards, You and Sans sit on a bench and looked up at the ceiling full of glowing crystals, shining like stars. He smiles while he was looking at them then looks down and sighs "Someday I hope I can eventually see real stars. Along with Papyrus too, I bet he would really like it. But...with the reset I don't think that's possible...I don't know how much more I can take of this."
You look at him concerned then put your hand on top of his and he tenses at the sudden touch then the both of you look each other in the eyes "I promise you there isn't going to be any more resets."
He looks at you with uncertainty "How can you be sure?..."
You smiled and let go of his hand "You know that Frisk did have the power to reset at one time, right?..." He nods his head in agreement at what you said "Yeah..." then you continued "So...when Gaster brought me here, they don't have that power anymore, this world is only a game..." He nods then looks down guilty like he did something wrong, you looked at him confused and worried "What's wrong now?" He answers you "You told me this before..."
You raised an eyebrow confused at what he said "What?"
"You told me that this was just a game, but I overreacted and tried to kill you...I'm sorry."
You felt your whole body frozed at what he said "I-I don't remember any of that..."
He sheepishly rubs his head "Heh...yep, if dad hadn't stopped me, I would have made an horrible mistake."
You smiled at Sans, feeling completely embarrassed "Can you excuse me for a minute?"
"Uh-Sure?"
You replied sweetly to Gaster (...Hey Gaster~)
What girl? I'm trying to rest, after what you put me through...this better be important!...
(Oh nothing~ I was just wondering why I can't remember the conversation I had with Sans before! Did you do something to me?!)
...He answers guilty...I did took over your body for a moment, which is why you don't remember anything...
(Gaster!)
...Hey if I didn't, you would have been dead!...
(Thank you for helping me, but next time a little warning would be nice!)
...Sorry...
You looked back at Sans "Sorry about that!"
He grins at you "No problem...So you were saying?..."
You remembered what you were trying to tell him "If Frisk or anyone have died right now then that would have been the end..."
His eyes widen in realization "That's why you refused our help, if we had fought Chara we would have been killed!"
You nodded your head "Yep...Chara would have hit you guys in one hit. That's how strong they are..."
Sans looks down uneasy at the information you gave him then you reassured him "But I think I have an plan so that Chara can never show up again..."
"How..."
You smiled and winked "Don't worry, I always have a plan.~"
He laughs a bit at your answer, and grins a little starting to feel a little better, then he takes out a ketchup bottle then starts to drink it. After a few minutes, you turned to look at Sans while he was drinking it and randomly blurt out "So do you have a crush on anyone?"
His eyes widen then he suddenly spits out some ketchup and starts to look flustered "U-Uh...Tibia honest I didn't think you would suddenly say something like that." You look at him teasingly and smirked "So you do like someone~...Who is it?"
He starts to blush an deep blue shade on his cheekbones then stutters "U-uh..." then he laughs nervously and quickly creates an portal then jumps in it. You look in disbelief at what just happened "Sans! You can't use portals to escape your problems all the time!" Then he quickly opens the portal and pops his head out then gives you an smug smirk and quickly said "Yes I can!~"