I am looking for a word to describe the kind of person who likes suffering or pain due to the relief that comes after it.
The closest word that I can think of is masochist.
- Psychiatry. a person who has masochism, the condition in which sexual or other gratification depends on one's suffering physical pain or humiliation.
- a person who is gratified by pain, degradation, etc., that is self-imposed or imposed by others.
- a person who finds pleasure in self-denial, submissiveness, etc.
Generally speaking, a masochist gets some kind of pleasure from experiencing pain.