Sh[in]e

One day, Lillie awakens in an unknown bed next to Sol, a man she's never seen. He also doesn't know how she got there, but he assures her that it is his bed and bedroom, and that she wasn't there the night before. She doesn't remember anything, nor carries anything on her... not even clothes.
The boy's stepmother, a woman too keen on social standing, bursts into the bedroom, misunderstanding everything, and he lies by claiming that Lillie's his betrothed, since he is sick of his stepmother looking for a wife for him.

The protagonist and Sol decide to fake their relationship and live together, at least until she gets her memories back.

[translated from Strawberry Translations]