Because it's decoupled from the constraints of real-world physics and biology, animation can provide characters who are impossible in real life. This allows for character designs, movements, and expressions that can be very effective at embodying archetypes and conveying supercharged emotion. Used well, this can lead to extremely compelling characters with whom it's easy to feel a bond.

Each character below is the waifu of her listed animation. But there can only be one true Animation Waifu. The other waifus are only Harem Tier on the overall Animation level.

Waifu Tier
The best of the best. Only one character may be in this tier for a given work or medium. This character... is Mai Waifu.

Harem Tier
The characters who, while not quite waifu material, rise above the rest.