The night before the wedding, Derek called Stiles and asked him if he wanted to go for a ride. Stiles was elated.
"Sure," he said.
They drove out to the woods, to a popular make out spot. There were a few other cars parked at a distance from Derek's vehicle. He parked the car, and turned to Stiles.
"Are you ready for the big day tomorrow?" Stiles asked him.
"Yeah. I got Laura to help me write my vows, and my suit is all ready to go." Derek said, taking off his seatbelt.
"Are you nervous?"
"Yup." Derek admitted.
"Wanna make out?" Stiles asked, raising his eyebrows at Derek. Derek laughed.
"Of course." He said.
They got into the backseat, and they both took their shirts off. The backseat of the camaro was large enough that they both could stretch out comfortably. Stiles kissed him, as they lay together.
There was a sharp rap on the window, and someone shone a flashlight into the vehicle. Derek's eyes snapped open, and stared at Stiles.
"Alright, people." A voice said. "Clear out."
Stiles choked as he recognized his dad's voice. "Dude, my dad's out there!" He whispered frantically to Derek.
"Does he know we're dating?" Derek asked, pulling his jeans back on.
"No." Stiles said, his eyes growing huge. Derek handed Stiles his shirt.
"Get dressed." He said, as the Sheriff rapped on the door again.
Derek opened the car door, and stepped out. Sheriff Stilinski looked surprised to see him, and he gave him a quick nod.
"It's Derek, right? Allison's fiancé?" He said, glancing at the fogged up windows of the backseat.
"That's right." Derek said, tugging his shirt over his head.
"I'm gonna have to ask you to move your vehicle." He said. "Excited for the big day tomorrow?" the Sheriff asked.
Derek nodded. "Yeah." He said, getting into the driver's seat. The Sheriff started to walk away. Stiles got out of the car, and opened the passenger door.
"Get in," Derek hissed at him. The Sheriff turned around, and saw his son.
"Stiles?" The Sheriff said, confused. "What – " Sudden realization flashed across his face, as he walked back to the car, and jerked Stiles' car door open.
"You're sleeping with my son?" Sheriff shouted, staring down Derek. "Stiles, for god's sakes. He's getting married tomorrow! To Allison – one of your friends!" He yelled, glaring at Stiles.
"Dad, stop shouting. It's complicated." Stiles said, slinking lower into his seat.
"Sheriff, I'm betrothed to Allison. It's a peace treaty between our two families." Derek told him. "Stiles is my boyfriend. Allison is Scott's girlfriend. It's complicated." He said.
The Sheriff stared at them, confused. "She's dating Scott, and you're dating Stiles?" He asked. "That's a very open relationship."
"I don't love her. We're only friends. The only reason why we're marrying is to protect my pack from the hunters." Derek said.
"Oh." The Sheriff said, rubbing the back of his neck. "I'll see you at home, Stiles." He said, walking back to his car.
Stiles looked up at Derek with relief. "Whoa. That could've gone alot worse." He said, putting his plaid shirt over his t-shirt.
Stiles and his dad drove to the church in the Sheriff's vehicle. The wedding was in half an hour, and Stiles had insisted they leave early so he could get a good seat. He also wanted to talk to Derek before the wedding.
Stiles dropped his dad off at the front doors of the church, and drove through the parking lot looking for a parking spot. He ran up the church stairs, noticing for the first time the tall, burly man standing guard at the top of the stairs. The man stepped in front of Stiles, blocking his path.
"You need an invitation to get in." He said, staring down at Stiles.
Stiles looked taken aback. "Wh- What?" He said, mouth dropping open. "I have one."
"Show it to me, then." The man said, crossing his arms across his chest.
Stiles looked around, and realized his dad must've already gone in the building. Crap. Stiles quickly dug through his pockets, but he came up empty.
"Please!" He begged. "Go ask the groom, he'll let me in!"
The man didn't budge. "I'm under strict orders from the Argents. No one gets in unless they have an invitation." He said, sneering. "No wedding crashers allowed."
Stiles glared at the man. "I'm not a wedding crasher – I came here to see my friends get married." He tried to dart past the man, but was caught by the arm.
"Get lost, kid."
Grumbling, Stiles put his hands in his pockets, and started to walk down the stairs. There must be another way in, Stiles thought to himself.
He walked around the side of the building. Nothing. Stiles finally spotted an opening at the back of the building, a tiny basement window. He knelt down , and pried it open. The window was just big enough for him to crawl through, and drop down to the floor.