Yoongi:
You kept bugging him wanting to go to the beach he kept rejecting until he finally gave up when you arrived at the beach he didn't really pay attention to anything until he turned his head to look at you his eyes widen seeing your abs for the first time when you get home you are not walking tomorrow.
Jin:
He was reading a book quietly until he heard you shouting 'we're going to the beach' it was a hot day after all so you agreed to go with you the second he saw your abs his mouth watered he's definitely going to find other ways to see you shirtless you were just so sexy to him.
Hoseok:
Although he doesn't want to admit it he really wanted to see if you have abs or not he didn't care if you didn't have any he just wanted to know but he didn't want to sound like a creep so when you asked to go to the beach he took the opportunity to see your abs once he saw you take your shirt off he'd be staring at you and drooling at how good you look.
Namjoon:
It was really hot this morning so he put a tank top he didn't want to be the only one with their shirt off when he saw you walking down with no shirt he was hypnotized but then he took his tank top showing himself off too.
Jimin:
We all know behind that cute face there's a set of muscles he always bragged that he had a better body than everyone you got annoyed and took your shirt off when he saw your abs he shut his mouth knowing he's been beaten at his own game.
Jungkook:
Like Jimin he has a cute face with a button nose but under his shirt, he's buff as fuck especially on hot days he likes to take his shirt off to tease you but you beat him to it you took your shirt off first his eyes widen he didn't know he got a boyfriend like you and boy was he lucky.
Taehyung:
He's not the one to show off his body but to tease you he'll do it any time possible like on concerts when he saw you in the crowd or when no one was watching he'll lift his shirt up a little maybe show his V line a little too but when you two were alone at your house you decided to tease him back by 'accidentally' spilling something on yourself you would rip your shirt off instead of taking it off when he turned his head lets just say you were limping the next morning.