Himouto! Umaru-chan, Osake wa Fuufu ni Natte kara Recommendations
Both mc's are normal... until they drink/get home. In Osake, the mc gets extremely drunk when having even a bit of alcohol and doesn't want anyone to know. In Umaru-chan, the mc becomes a complete 100% otaku when she takes a step indoors and relies on her brother to do everything for her.
Chisato Mizusawa and Umaru Doma is are similar character.