anyone knows any manga similar to this manga's plot?

This is somewhat similar:
I was Told to Relinquish My Fiance to My Little Sister, and the Greatest Dragon Took a Liking to Me and Unbelievably Took Over the Kingdom manga

Sorry forgot to put the Link: http://www.mangago.zone/read-manga/i_was_told_to_relinquish_my_fiance_to_my_little_sister_and_the_greatest_dragon_took_a_liking_to_me_and_unbelievably_took_over_the_kingdom/

"I Swear I Won’t Bother You Again!"...which has similar setting

thanksss