A/N: You guys had a date but you were running late. He came to check on you when he noticed the door to your room was unlocked. So he walked in and saw you changing.
Lucifer: His face would start heating up and he would get a smirk on his face. Realizing that he is having lewd thoughts, he would exit the room immediately. You would be left in a blushing mess while he tried to calm himself down after seeing your exposed body.
Mammon: He would notice that you are only half dressed and immediately close the door. He would run into his room, lock the door , and stay in there all day. The next time he saw you, it was pretty awkward.
Levi: He would get a bloody nose and faint. You would mentally face palm.
Satan: He would be a gentleman and apologize. He would then wait outside your room until you came out. Then you two would go on your date and it would be like nothing happened.
Asmo: It's Asmo. What do you think would happen. Immediate make out session.
Beel: He would stare at you for a while and then close the door. You would both be a blushing mess. Beel would be acting weird for the rest of the day. He would hardly eat anything too.
Belphie: Would smirk and start touching you. He would then propose a make out session.
Diavolo: He would cover his eyes, apologize, and run out of the room. When you saw him again, you would give him a light scolding about knocking before entering. He would make it up to you by cuddling you all day.
Barbatos: Would smirk and start admiring your features. You would have to push him out of the room before he tried something.
Simeon: Would smile and start complimenting you. You would have to ask him to stop staring and leave while you got changed. He happily obliged and waited outside. But some part of him was wishing he was still in there with you.
Luke ( Poor baby ): Saw you and started freaking out. " Y/N! Please lock the door!" He said. He then ran to his room and it was awkward between you guys for about a week.
Solomon: Just like Belphie, he started touching you and proposed a make out session.