Don't think we're ignoring shonen romance, as here's a wretched little one-shot example from the creator of D.N. Angel.
RIZELMINE (Rizerumain), by Yukiru Sugisaki. First published in 2001 and first published in North America in 2005.
PLOT:
Tomonori Iwaki is having a very bad day. It began when he learned that the teacher he's been crushing on is getting married. It only got worse when he came home, only to find a tiny, obnoxious little girl named Rizel claiming to be his wife. Rizel is a secret government experiment, a being who needs to learn about love to further her development, and her "dads" (who are totally not government spooks) easily bribe convince his parents to go along with it. Rizel loves her new husband, but Tomonori wants nothing to do with her and his rejections come with explosive results. Things only get more chaotic from there, as some of Tomonori's classmates, an American-made knockoff of Rizel, and a coma threaten to part the unwitting couple.
