
He didn't straight up say he cheated, he said he practiced so maybe he meant he did research.
I'm just gonna think of it that way because then it would ruin the story for me if I was wrong.

It might be bitter, but actually it was a good move on his part to be honest. Ryouta has been fixated with the same man since he was 12, don't you think it's fair that he practices, and thus gets experience to make sure his feelings for the uke are genuine, and aren't pure fixation? Because of this I don't think that the uke being an older guy and all would mind. This way he won't have to deal with feelings of insecurity over whether Ryouta is truly in love with him and isn't just with him because he has been his only experience. (〜 ̄△ ̄)〜

Okay, I re-read this post and I have a question... How can you cheat on someone if you both are not in a committed relationship together. Let's say I'm single and am deeply in love with guy A, but he's clueless that I exist. So, I go on dates and even sleep with guy B and guy C. I've made no steadfast commitment to anyone thus far - I'm simply "playing the field"... am I cheating and who exactly am I cheating on?

See, I feel the same way. A lot of fans tend to place the term cheating on situations that don't seem valid to me. This was the whole reason for my question. I'm of a different generation - I'm old enough to be most fan's mother - and I thought I was missing some new and important information, to be honest. I grew up between the 60's "free love" and the late 80's "AIDS crisis". And I grew up around nothing but gay couples and gay men (In NY and NJ) so promsicuity was "fashionable". So, I kind of have the mindset that, if you put a ring on the finger - or make a vow of commitment, even if it isn't "official" - then cheating is a No-No. All other situations are fair game, Dating; sleeping together; living together... commitment isn't implied, it is explicit. "I want to be with you and only you forever or until we break up. And I want you to be with me and only me for the same period of time." "Agreed?" "Agreed." Thus, commitment. "Wanna date?" or "Wanna have sex?"... no commitment. Yet people still act like this is some crazy idea.
Thank you for answering my question cadidly. And, btw, I love your screen-name.

Oh, wow, haha. I honestly know nothing of that culture, since I was born in '96...
See, when put in such terms of an explicit commitnent, it makes sense; people think that boundaries in relationships are implied, and it's like... no, it's not. It's both parties' job to set expectations for the relationship. Haha, but maybe our views are too "open" and "loose".
Btw, thanks for the compliment, haha.

They weren't in a relationship per se, but the uke and seme promised to wait for each other, especially the use. Not to mention, your example doesn't hold weight because it's not like either of them were in love with the other without the other's knowledge. It was a completely mutual relationship and understanding between the both of them. I would totally call it cheating, or at the very least I would be extremely annoyed and upset. Why? Because the seme went to lengths to have the uke watched and kept away from other potential relationships, and acted in a way to make the uke pine after him for years. Yet he could go and sleep with others? All under the guise of gaining experience? That's an imbalanced and totally unhealthy relationship.
Spoiler warning!
Ok like both stories exceptttt... in the first story... dude that ex really needed to get arrested or at least outed to his wife/higher ups. Second story I loved until the last bit where I realized.... the seme was "practicing" *cough cheating* on the uke for all those years and still had the guts to keep the uke for himself!??!!?!? Grwarrr I get that the mangaka tried to make it comedic but I really hate cheating in these sort of situations T.T