Waifu, a term used for fictional characters in (typically Japanese) animations, games and comics that a person feels attracted/attached to. Being (usually female) fictional characters, waifus come in a variety of forms which include: ridiculously sexy human women, adorable monster-girls, anthropomorphic red blood cells and zombie idols. No, I am not making up the last two examples.
People often ask why fans/consumers of (typically Japanese) works of fiction are so attracted to fictional waifus. To some extent, I can understand their point. Waifus are undeniably fictional and will never be real no matter how much some may wish to believe otherwise. Also, there is no denying that rejecting a “3D woman” in favour of loving a “2D waifu” is rather “counter-reproductive”.
Before we answer the question about people liking waifus, let me ask this question, “Why are some people so obsessed with certain celebrities?”
Although celebrities are “actual flesh and blood humans”, they are not necessarily much more “real” than a completely fictional waifu when it comes to personality. After all, many of these people put on an act while “on camera” to be liked or accepted by the general public, especially their fans. While there are certainly those to are mostly honest even when on camera, there are also those to are essentially “completely fictional” while in public. Therefore, as strange as the idea may seem, liking a completely fictional waifu is actually not that different from liking a celebrity since, ultimately, someone is liking an idealised individual.
Waifus may be completely fictional but they are, quite ironically, also completely “true” in the context of their fictional existence unless their creators decide otherwise for the sake of plot twists or character development. When one considers how disappointing reality can be, it is surprisingly easy to comprehend the appeal of an idealised individual who is entirely fictional and yet is also entirely true within the context of the character’s fictional existence.
At any rate, that’s just my opinion/observation about the appeal of fictional waifus.