When something is both arrousing and horrifying at the same time, it can be more horrifying or more arrousing or perfectlyin between, but it still counts as being horrousing.
Friend: OH MY GOD THATS HORRIBLE...No wait its actually a bit arrousing..no horrifying...I DON'T KNOW WHAT IT IS.
Me: Are you Horroused.
Friend: Yeah that works.
American Dad Episode where Steve grows huge sexy breasts.
Movie Doghouse where there are some sexy female undead, zombies.