I wasn't able to contact the owner of this product, but would anyone be able to tell me who the character is/what they're from? It would be much appreciated! Thank you!!
Sakamaki Laito from "Diabolik Lovers": he is wearing the same suit and the the same look on his face also same hair color and eye color. I couldn't find this keychain anywhere but if you look up his name there is the same image on tumblr (he is a boy and a vampire by the way) this must be a Halloween costume. Anyway here is his image on zerochan :)
This could be Alice, from Mahō Shōjotai Arusu (or Magical Girl Squad, or Tweeny Witches). However, there are some obvious differences between the image in the question and Alice in the anime. I'm not sure if these stem from a stylistic choice on the part of the artist who made the product, or if I am wrong about who this is meant to be. As of Mimo's answer, I can confirm I was definitely wrong.