haematophilia
Haematophilia within BDSM, refers to the sexual interest in blood. The fetish can be satisfied in many ways, usually through visual exposure. Though, ingestion of, submersion in and withdrawal of blood can all be ways to fulfill one's desires related to the fetish. A common misconception about haematophilia is that it can be triggered by period blood, this is in almost all cases, inaccurate.
Person1: why was he breathing heavily throughout the lab practical where we withdrew blood?
Person2: he was horny, he has haematophilia!
Person2: he was horny, he has haematophilia!