It All Makes Sense.

Ailsa had finished the preparations for the Immortal Grade Realm Heart long ago. The Godhead of a Sky God that had been on the verge of crossing the final barrier into the True Sky God Realm was more than enough of a catalyst. 

Ryu found himself sitting in meditation, shirtless. A complex jade-green formation was drawn around him and Ailsa sat to his back, her palm resting on his spine. A pulsing power began to emanate, surging across the Moon World. 

An Immortal Grade Realm Heart would only be a minor boost to his battle strength from Ryu's understanding of things. Its main function would only be allowing his cultivation speed through the Immortal Realms to skyrocket, but Ryu had no plans of improving his cultivation any time soon. As such, it could be said that the only reason Ryu was wasting time doing this was so that he could maximize his chances in all aspects.