You may be psyching yourself out. The more you worry about needing to be in charge to climax...the more likely you are to mentally and subliminally try to make that happen.

Try to relax and enjoy the experience. You're with someone you care about, that cares about you. Enjoy what's happening and orgasm whenever and however you need to. It'll cum.

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Though I am different from you,
We were born involved in one another.

For it was not into my ear you whispered, but into my heart. It was not my lips you kissed, but my soul.

Complete surrender should not just come at moments in which one faces overwhelming odds, but in the calm when it seems one is personally in complete control of one's life.