I don't remember any title's Things

Istg i kept trying to search for it but still couldn't find it
A few thing i remember abt this manga is that it's yaoi, omegaverse, the uke is giving the seme 1 week (?) to make him in love so that he wouldn't remove the bond thingy. They were bestie or classmate something.

It's shoujo
The fl has white hair
She's some shorts of image of a white lily (?)
She has some illness that she can only live for a shirt time, she had bad relationship with her family but it get fixed up during the time she isolated herself.
She made friend with dark hair knight ( Or duke something idk) cus she said she had never had a friend.
I swear i don't remember the title at all.