I think inui was trying to hold it. It hurt my heart when he said he doesn't smell anything, but at the same time tatsumi tried to cheat (reason or not, it cant justify).
maybe he was exposed to his pheromones long enough to build up resistance. since his pheromones didnt affect only ppl who loved him but random people. he is heartbroken and feels betrayed. but i believe he still loves him and thats why he is hurt so much by this betrayal..
Inui's nose was stuffy because he had a cold. That's why he couldn't smell Tatsumi's pheromones.
oooooh! DON'T SPOIL MEH! I'm speculating but I don't want to have the cake and eat it too! not yet, at least XD
It means Inui doesn't love Tatsumi anymore and that's why he can't smell his pheromones ╥﹏╥
Somehow, it breaks my heart.
Unless, Inui was really trying to control himself cause he's still mad at Tatsumi's cheating ass.
But I don't know why, I'd really like it if Tatsumi doesn't come crawling back but actually grows a pair and leaves Inui and find his own apartment, but we all know Tatsumi will probably beg and then they'd have great make up sex ╮(￣▽￣)╭