Dominate the Mountains and Seas, Start by Pretending to Be the Illegitimate Son of the Governor

[City + Classic of Mountains and Seas + Multiple Heroines + Fighting of Wisdom] There may be too many female characters, so don't join if you don't like it... The director of academic affairs mistakenly thought that I was the illegitimate son of the principal, the principal mistakenly thought that I was the illegitimate son of the county guard, and the county guard mistakenly thought... In short, I can be mistaken for anyone and any identity, but these are all fake.