A (typically) sexual arrangement between two consenting adults where one person is a companion to other other in exchange for--and contingent upon--some form of compensation.
her: you're hot, mr. man. seeing anyone?
him: e'yup. you, if you have the means to keep me.
her: how's an apartment all to your own, and i have the only copy of the key?
him: him... a sugar relationship. yeah. that'll work.
A person who strongly desires to be financially spoiled by a 'Sugar Daddy' or 'Sugar Mama' (usually in exchange for companionship and/or sexual favors), but can't seem to find a suitable partner.
Man, I'm a sugar baby out here with no sugar mama to be found, I'm just a sad, lonely sugar orphan, trying to get by in this world.