Ijiwaru-Ouji wa Mechakucha ni Aishitai.: Giji Shinkon de Ama-Ero Choukyou Seikatsu
Akaba's hardworking single mom just got remarried to a familiar man - Mr. Ono, who used to look after her when her mom was at work. But that means she's now stepsiblings with her first love, his son Hiroki! The only problem is that Hiroki immediately tells her he doesn't see Wakaba as a sister...or is that actually a good thing?
(Source: Manga Planet)