n. 1) A seemingly unattainable female that you finally get to have sex with after having had a crush on her for years.
2) A relationship (usually sexual) with a seemingly unattainable female, which boosts a man's ego, and restores his faith in the human race.
1) “I dug her for years, but she never paid attention to me; then all of a sudden, Boom! -I got a Rena.”
“I was feeling totally down and unattractive, then I had a Rena with girl next door and now I'm feeling like I can walk on air.”