Responses
Sure you mean this one
https://www.mangago.zone/read-manga/turning_a_crazy_dog_into_a_young_master/
But just in case
https://www.mangago.zone/read-manga/the_beast_tamed_by_the_villainess/
Yep I meant the first one. Thank you very much (●'◡'●)ﾉ
The FL is a saintess who works in castle and tames a prince and tries to make him civilised. The ML was a prince I think but went mad due to experiments or war