It's an ultimatum, not necessarily giving in.
He literally isn’t giving in, if something lol at Jaehyuk’s face in that last panel LMFAO.
This isn’t a classic chasing arc with the asshole begging the other person for a second chance, explaining them they understand what they did wrong and that they’re sorry, Jaehyuk’s chasing arc hasn’t even truly started yet. It has started in a sense that he’s realizing he wants to be with Garam, but he hasn’t realized his wrongdoings, doesn’t respect Garam’s wishes either, he still thinks the feelings he holds for him are only and purely sexual attraction and he "caught Garam’s homosexuality" #－.－). With Garam’s ultimatum, which is "have sex with me once but let it be the last time we interact", he’ll probably realize the conflict between him wanting sex out of garam but not only —> he also wishes for his company and spend time together and it’s going to be the REAL beginning of the chasing arc.
Hope this helps
Garam is one of the only few intelligent bottoms in those kinds of stories
you explained it well :D
His chasing arc was just beginning why is Garam giving in already