Nihilego is the perfect pokehusbando/waifu.
First of all, it' playful and childish. Just looking at it will fill you with happiness.
Second, it's a very strong pokemon. It can protect you without any problems, even if a fucking pokegod wants you dead, Nihi will wil for you.
And finally, Nihi can make a waifu out of you. Its poison is perfect for people that lacks self confidence or is depressed.
Once you get a nice injection of poison (preferably in the vagoo), you'll be happy and full of energy to hug your Nihi.
As a bonus, you can wear it as a had and look gorgeous. Girls will be jealous of you.
Truly, such perfect specimen cannot be replicated. Try to find a flaw. I dare you.