When someone is looking fine u say they are buff (London ting)

Very strong or having defined muscles, hot. Used mostly for guys.

A member of the volunteer public service (EMS, Fire, etc.) who is overly committed to their role, as in one who buys too many emergency lights or owns his/her own personal gear.

BUFF originally refers to the B-52 Stratofortress long-range strategic bomber. The enormous aircraft was extensively used for carpet bombing missions in Vietnam and as a first-strike or retaliatory strike nuclear weapon delivery vehicle during the cold war. The crews rarely referred to the aircraft with its real name, instead they used the acronym BUFF, for Big Ugly Fat Fucker.

(In MMORPGs) To improve the stats of another player by casting spells, as is typical of Acolyte and Cleric classes.

very strong and well built

Bonafide Ugly Fat Friend
Every hot chick seems to have one, either to make themselves look hotter, or out of sympathy for the said fat friend.