Being religious isn’t dependent on a religion, it is a fundamental state of mind in which one sees the fullness of divinity in all and everything, it is a deep longing for the state of oneness for being whole again.
Tantra says that the erotic act is an invitation for that sense of oneness, for it is within the union of the bodies that one can exalt the spirit to merge with the one. This art of lovemaking in the tantric way is revelation which rejoices the spirit and brings us closer to the one.