How to Be a Man

This series of manga is about a romance between the dimunitive Shingo and his friend Kumiko in different stages of their lives, from childhood to adulthood. It spans six different manga titles - 5 one-shot manga and a 10 volume 6th series that eventually wraps things up. It's well worth the time:

1. 130 cm no Dandy
2. Dodgeball wo Shiyou
3. Mirai Yousouzu
4. Step Up
5. Paris de Issho ni
6. Otona ni Naru Houhou (10 volumes) How to Become an Adult