Please help me find this manga, I've read this manga long ago, I forgot the title/name of the manga but here is what I remember. There is a clan/family with branch family and so on, branch family serves the main family, a young orphaned boy become an attendant to the daughter of the main family and learned ninja like skills to serve his lady. But the young lady turns out to be a body double of the real ojousama who has a big flower birthmark on her back. The birthmark only appears to their direct bloodline and the boy turns out to be a spy to avenge the death of his family.

I know i'ts not so clear and I tried searching for it myself but this is all that i could remember, hope that someone could help me, I really like to continue reading the manga

Teru teru×Shounen

Yes, this is it. Thank you so much, you just made my day. ?