system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does an orgasm feel so good?
gpt
Our brains are evolved to trigger a dopamine reaction to orgasming.  Dopamine is a hormone which makes us feel good.  Our brains use dopamine to push us toward beneficial behavior, one of which is sex, which leads to procreation.  It also is why rich food tastes good.