Dandy Dungeon: Legend of Brave Yamada

Yamada-kun (Age 36) is a programmer at a major game publisher. He hates his job. Alone in his apartment, deep into the night, he toils to create a game of his own: it's an RPG, and he is the hero, Brave Yamada! One day, he falls for his new neighbor Maria-chan. To nurture these feelings, adds Princess Maria into his game! Will they find love? (Metacritic.com)