Recommended reading for further study and exploration.

Sexuality:

The Art of Sexual Ecstasy by Margot Anand

The Fine Art of Erotic Talk by Bonnie Gabriel

The Heart of Tantric Sex by Dianne Richardson

The Lover Within by Julie Henderson

Sex for One by Betty Dodson

Sexual Energy Ecstasy by David and Ellen Ramsdale

Wild Nights by David Deida

For Men:

Male Sexuality by Bernie Zilbergeld

The Multi-Orgasmic Man by Mantak Chia

Tantric Secrets for Men by Kerry Riley with Dianne Riley

For Women:

The Clitoral Truth by Rebecca Chalker

For Yourself: The Fulfillment of Female Sexuality by Lonnie Barbach

The Multi-Orgasmic Woman by Mantak Chia and Rachel Carlton Abrams

Tantric Sex for Women: A Guide for Lesbian, Bi, Hetero, and Solo Lovers by Christina Schulte

Relationship:

Intimate Communion by David Deida:
An introduction to "sexual polarity."

Passionate Marriage by David Schnarch

Spirituality:

Ask and it is Given by Esther and Jerry Hicks

Conversations with God 1-3 by Neale Donald Walsch

The Essential Rumi, translated by Coleman Barks

The Red Book by Sera Beak