Ore dake Miteroyo: Onzoushi to Ikinari Shinkon Seikatsu!?

Synopsis

Suzuno works at a major stationary company to help pay off her parents' debts, until Watakai, the heir of the company, learns about it. "I can help you, if you marry me." He proposes marriage to Suzuno and pay off her debts! Suzuno hesitates at first, but she is eventually drawn into a sweet newlywed life! Suzuno, who is inexperienced at love, doesn't know how to act towards him, which only unwittingly makes him feel more possessive of her...? (Source: Berry's Bunko, translated)