I have been reading too much harlequin manga lately but want to reread this one, but all I can remember is that the man did not go to her graduation (I believe college) and instead got her a gift but the gift was not picked out by him but his secretary, who always choses ugly gifts to get back at him. This may be the same manga but not 100% sure, I think she also got him a tie with a dragon or something on it every year for his birthday.

Found it four minutes later.... It's Heartbreaker