
Can someone explain to me why inui also have the phenomenon? If they have the phenomenon what does that mean? Is it they want to have sex?

So the one with the disease (ex: person A) let out a pheromone which causes anyone who likes them (person B), to be lust driven towards them (A).
In this case the uke drink medicines so the seme won't get affected by his pheromones. But then the seme also suffer the disease which then affect the uke too and become as lust driven, if not more, because he really loves the seme too.
Whoever uploaded this,i just wanna say that I love you so much (=・ω・=)