Vulture

[Sarah]

Any one of numerous species of rapacious birds belonging toVultur, Cathartes, Catharista, and various other genera of the familyVulturidæ.

[Sarah]

(1)adj. Any person/thing who picks apart/[scavenges] through an object or place to [obtain] useful or working parts/pieces to [benefit] himself.
(2)v. the act of picking apart/[scavenging] through an object or place to [obtain] useful or working parts/pieces to [benefit] oneself.
adj. Vulture
v. Vultured, Vulturing
adv. Vulturingly

[Sarah]

a guy who would [woo] a vulnerable girl who just came from a bad relationship or had a bad break up.

[Zipporah Schumaker]

A person, business, corporation or political body who/whichpreys on the misfortune of others. These people/businesses/[political parties] often present themselves as charismatic, and [commence] engineering involvement with people, businesses, communities or nations at the early signs of their [downfall].

[Magaret]

(verb) to actively wait until a relationship ends, and then [swoop in] and attempt to establish ones own relationship.
However, no sabotage is done, as in a vulture [circling] above an animal (the relationship) dying in the desert. [Vultures] are scavengers, and let the relationship fall apart naturally so they dont feel guilty (although guilt may be present regardless.)

[Kit]

A friend who would have sex with your gf/[bf] or [spouse]. A friend who would would get your date [your ex] knowing that you still love them

[Dave Paprocki]

A large bird of prey with the head and neck more or less bare of feathers, feeding chiefly on carrion and reputed to gather with others in anticipation of the death of a sick or injured animal or person.

[exinilu]

one who takes the [leftover] kills in halo. One who takes them frequently, and as much as possible. One who hears, [Killtacular] [killtacular] killtacular.