The deal is the latest in a long line of acquisitions by DeeCash. Other recent deals include the company's acquisition of MeatCash and a partnership acquisition of Rude.com, both in May.
In recent months, DeeCash also acquired Mayor's Money, JoinRightNow, BadGirlBucks, NichedSites, EliteDollars, EpicCash, JasonAndAlex, MILFCash, PureMeds and TripleXCash.
Terms of the latest deal were not disclosed, and representatives from the programs involved were not immediately available for comment.
To mark the acquisition, however, DeeCash issued a press release announcing an offer of $100 per sign-up on STFU Cash through the end of June, lifetime $50 per sign-up on all price points (trials and $1 joins included), weekly payouts and weekly updates.
STFU Cash - created by Chief Executive Officer Steve Krikorian, Chief Operating Officer Vahe Haroutounian, Chief Financial Officer Allen Yeganian, and Chief Technology Officer Edvin Aghanian - was launched in April.
The owners of STFU Cash also owned the review sites MyAdultReviews, RealityPornSearch, PornDraft and KinkyStyle.