Toshiue no Hito(2004)

Toshiue no Hito

The woman Tsutomu encounters in college was older and smaller than he is, and for some reason, looks like the same girl in his dreams. The heart-pounding love affair between him and the "older woman" begins.

(Source: Animewaves)

Includes 2 bonus story: Ageha-chan's Lost Child (vol.3) and Stolen Breasts (vol.4).
Includes H na Manga ga Dekiru made (Hなまんがができるまで); Young Animal Arashi Vol.11