Virgin Night is packed with heartwarming; this is Erotica that wears its heart on its sleeve.
The title story, in a three page sequence, puts any other manga to shame in handling a person's first time.
Azumi: It's okay because it's you, Yuzuru-kun.
To elucidate a bit further, Yuzuru is panicking because Azumi's in pain from initial entry, and so tries to withdraw. Azumi, however, holds him fast there so he can't withdraw.
Nadeshiko Innocence ends with a date that contrasts with the ones we see earlier in the story in the best way possible.
The last page of Shall We?. Especially if you've ever felt that initial rush of sexual attraction start to go deeper.
Also consider that at the beginning, all Yoshito had really noticed about Ami was how constantly bored she looked in school; she even looks that way as she and Yoshito are just beginning to get under way—the first page and most of the second, at least. That last page is implied to be a fair bit after the August break—after their assignation—and she looks utterly vitalized now. Yoshito isn't the only one looking at the world in a new light.