I like the subtle revelation that it's Maki's birthday in the end.
Karuha is now officially my favorite artist/author. She(her Pixiv says she's a female) makes her characters realistic. So far, I've only read her Nicomaki doujins and I don't know if she makes anything other than those. But she's still my favorite. I like how she portrays the emotions of her characters, their insecurities(evident in her previous work) and all. Her art is great too.