Barajou no Kiss

Most girls are crazy about jewelry, but not Anis Yamamoto(Barajou no Kiss). Not since her father gave her a rose choker as a child, claiming it was a protective amulet which would safeguard her from harm; however, if she ever took it off (a feat easier said than done!), she would be afflicted by a “punishment” of some sort.
Not like it matters to her though, since the attention it attracts around school from faculty and students alike isn’t something she’s particularly fond of.
But after a certain incident causes the choker to disappear, she realizes that this punishment her father spoke of might have been a bit more than she bargained for!
Although the female leader(Barajou no Kiss) starts off as an outcast because of her ghostly appearance, she gradually begins to make genuine friends by simply being herself and her kindness.
And she falls in love with the most popular guy in school who is genuinely nice, reciprocates her feelings, and is the first person who sees her for who she really is, though she's too socially awkward to realize this at first.