Who's your favourite greenflag that turns into a redflag ?

mine is freaking Lee Jaeyi from Scammed and Rammed (i still love him and the author but sobsob my heart was broken)
I know he's gonna crash out sooner or later but i would've never thought the purest innocent cutest baby in the world would grape his beloved

anyway, i'm waiting for the s2 woooo, the regret and chasing arc better be satisfying