Yosselyn's Manga

Guy (uke) come from the future, for some reason he is now on the past, which means he is totally lost and scared, he finds a prince who has the exact same face as the uke. Prince is really busy so he take in the uke in exchange replace him and do his "prince duties". One day an emperor(seme) comes to visit the country and fell head over heels with uke, seme offers uke a proposal that would benefit the country in exchange of sleeping with him, uke accepts. 1 yr later ukes country is invated, prince is killed and uke flees to semés country is search of protection

Female lead is in love with childhood friend, but this friend is going out with her best friend, heart broken and tired of having an Unrequited love she does something she would never do otherwise, she goes to a bar and has a night stand with a handsome guy. A few months later she finds out she's pregnant, and the dad is her student's uncle, who's not only rich but also owns the school she works for and he wants to marry her!