Mukatsuku Aitsu ni Motto Naderaretai.

Yuzuki and his co-worker Ayase, who used to fight all the time whenever they saw each other, are now lovers. They still argue constantly, and sometimes he still hates him...! But when Ayase's hands caress him and he feels Ayase's clumsy tenderness and affection, his face and body melt instantly... (Source: Splush, translated) *Note: Includes 2 extra chapters.*