Koi no Towaltz

"I'm here to pick you up, will you marry me?"

Yuuichi, a poor college student, spends his days studying for a scholarship and working part-time. One day, the world-famous supermodel Reo Ichinose visits the café where Yuuichi works. As the store goes crazy at the unexpected celebrity appearance, Reo tells Yuuichi, who is completely clueless about fashion trends: "I've come to pick you up," and proposes to him...!? Yuuichi has no recollection of him, but Reo insists he has come to keep his promise to Yuuichi.

(Source: Ichijinsha, translated)