[Metako] The Slime's Gratitude (Bessatsu Comic Unreal Tasha Henshin Shite Narisumashi Yuuwaku Hen Vol. 2) [Decensored] [desudesu]

When his cold sister-in-law Reina leaves on a trip with her husband, Kazu's summoned slime—Mick—decides the best way to repay its master is to transform into her perfect double. What begins as teasing comfort spirals fast, with the slime-as-Reina on her knees cooing that he feels better than Youta ever has, and when Kazu blurts out a wish that she were his classmate instead, the transformation answers—school uniform, swelling chest, and a climax that leaves her overflowing. A shapeshifting impersonation fantasy where a monster girl's gratitude knows exactly how far to take 'relief.'