Hony Pead is the romantic pairing of Pony Head and herself.
Sleepover - Pony Head reveals she has a crush on herself. Since she is herself, that makes the crush mutual, making it 100% canon. Also, she reveals her "crush" during Truth or Punishment, and since there is no punishment, it's 100% real.
Canon Probability Edit
Ponyhead is very over confident with herself so she may not end up in a relationship. Ponyhead was recently in a relationship with Seahorse, however they broke up. Their relationship is an on-and-off one, so they may get back together.