There was a knocking at his door that awoke him from his nap.
"Door's unlocked," he yelled as he put on his undershirt.
Fionna peeked in through his door, and walks in slowly.
"What're you doing here, kiddo?" Marshall asked.
"I just fought a few monsters nearby your cave. It started raining, and Cake ran home without me. So I had to finish them off alone and thought I'd come here to stay. I'm a little wet though, do you mind?"
Marshall didn't even notice at first, but once Fionna mentioned it, he noticed he could see right through her shirt. A lace bra. Nice.
"Could I borrow some clothes, I don't want you looking at my tits all night." said Fionna. It caught him off guard, but he nodded and threw her his red flannel shirt.
OhmygodOhmygodOhmygod. She's undressing right in front of me, he thought as she took off her shirt and put on his flannel. All these feelings he was getting was extremely weird, since he's known Fionna since she was eight years old. Now she's 16, and he's 17... still.