@Gojo Satoru
"The fallen duke and the knight who hated him" That's all I know that's very similar to this type...European historical themed, more shounen ai and cute romance.
Other options that's somewa this type of historical themed are "Savation, The Rogue Prince is secretly an omega, How to raise a victim, Eternal contract?!! But these aren't as cute and sh** like this one to me but yea.
but thanks