I was looking for this kind of story without so much emotional depth (for now, because I'm usually a sucker for angsty things), but this is what I call story with potential. Ahh, they should really have gone more into Kikusui's past, and all those feelings of his about being abandoned...
The reason this manga's quite okay, actually, is because the artwork is gorgeous, I just can't stop looking at it! It even helps making the hot scenes sexier! The first kiss, even being just a kiss, is really hot and it gets better by the second.
As for the characters, Kikusui is to die for, and I love his personality. He's the kind of pushy, yet it's-only-because-I'm-into-you thing, so...yeah, he's my kinda seme, I can't help but love him. That's the formula I like for a younger seme: he's gotta have more experience even though he's younger and be immature as to never leave the uke alone~!
Erimoto is a little boring. He's not whiny, at least, and he could even be called cold at parts, but he annoys me because of all his insecurities where there's no place or reason for them.
As for the short story...wow, the seme's personality really surprised me! Even though he acts all grown up and chases after the uke, Yuu is actually quite mean! He gets jealous and then just leaves Nanatsuki crying! That's unexpected, semes in yaoi would usually act different. But he's likable!
Oh, and Nanatsuki's so pretty he looks like a girl!
Also, that "call out my name and not his was really cute! And I like how the story ends with hope of happy times ^^~
In general, it's too predictable and common, but enjoyable.