@ksyhan3h I seriously have no damn idea why so many people are confused by this. It is obviously referring to parental love, how if your child makes something to give to you, no matter how shitty it is, it's precious to you. Hell, the manga even refers to it in one of the chapters "you can't place a value on memories and emotions"
@Pancakeza yeah, it's one of the better romance mangas I've read, it got unnecessary hate at the beginning because of the cut pages and cross-dressing though, sad.