Definitions by Yummy89766

Sin-a-bun 

The sexual act of maneuvering your buttox in a circular motion to create a dump that appears in a cinnamon roll shape on your partner's chest and finishing it off with the semen icing.

Ex: Last night I received a steamy sin-a-bun for dessert.

Sin-a-bun by Yummy89766 May 17, 2010