vulture

1. a person who dates/enters into a relationship with another person who is much older/ancient, such that the are figuratively circling the person, waiting for them to die

2. a young person waiting to collect inheritance from a much older person or group of people

Bill "Did you hear Jim is going out with that cougar?"
Phill "Yeah, he's such a vulture. Isn't she like 90 or something?"

I only visit grandpa because he is rich and old, does that make me a vulture?