Was his dick really that small? In it's erect state it looked pretty average or maybe slightly under average, but not micro penis small. Of course, for a hentai protagonist that's really small, but I don't think the other boys had so much bigger dicks (well, except the two previous boyfriends of the girl)...
Truly an intriguing title.
I feel like I've seen a similar story before, with the guy having a tiny one and the girl having a small one, and them being perfect for each other...So even with a small dick, the Hentai gods haven't abandoned him. Great ending too.
That creampie tag though...
On the contrary, as I interpret the dialogue, the girl only has sex with him because he's "just the right size for her", otherwise, she seems to want little if anything to do with him. I volunteer: there are other 'fish in the sea' who will like you as more than just being the right size, protag-kun ... Move On.