at the beginning of the chapter we have jaeyoung’s psychiatrist explaining how the drug affected jaeyoung’s feelings and why he is incapable of feeling happiness: because of the drug incident he can’t produce serotonin. so, to bring his feelings back, he will proceed with an alternate route based on dopamine (dopamine instead of triggering happiness it triggers pleasure). long story short, he will boost the dopamine mechanism as an alternative.
then we have jaeyoung’s band members. seungmin basically planned the whole meeting behind jaeyoung’s back so that jaeyoung realizes they are not actually mad at him because of how things went with the disbandment (yk jaeyoung feels he is partly responsible of it so he thought they hated him). seungmin also planned this meeting because he knows that jaeyoung used to have fun when he was in the group.
and lastly, we don’t really know about the missing member, we’ll just have to wait and see. hope this long ass explanation helps lol

embarrassed to ask but can someone give me an explanation about the start of this chapter and what happened with the last member of the group?? was happy not able to feel happiness even before the drugs or because of the drugs??