Imo, 1. Shunpei learned to love being uke and loved to make Fumi happy however he can.
2. Sensei is not ready to i troduce the couple into a versatile one. I think it has to do with the fans. I believe they have this rankings or stuff like seme and uke ranks and most probably many fans are not ready for a switch. Just my opinion tho. But i'd really love them to switch sometime in the future.
Mmh, yeah, I just thought about how in Haru wo daite Ita it was a sign of their mutual love, which I found kind of sweet, even though I prefer Iwaki Uke. And since Fumi seemed kind of into it I found it a bit sad. But I get it.
It worked out so well in Haru wo Daite Ita!
I still want shunpei to be the seme because he is so manly.. ♡
I'd like to see them switching to from time to time too.
I like the fact that it's Fumi who is the seme because it's unusual: when you start reading the manga and you see Fumi's and Shunpei's behaviours, "normally" you think that it would be Shunpei the seme. And when you continue your reading, you see that no, Shunpei really became the uke.
I think the mangaka was right to draw the things like that. However, I still would want to see Fumi experiencing the cat's role.^^
What I don't understand is, doesn't Shunpei want do do Fumi too? I mean, some people are just total bottom... but to pass on a chance like that. Baffles me. (remember reading a chapter like that)