What you've experienced is female ejaculation; it's a fairly rare gift/ability, and for the women who are capable of it, it's also indicative of an intense orgasm. Just lay down a towel or two if you're concerned about the squirting, and enjoy the ride.
You may find it easier to take the lead if you don't think of it as initiating sex--or taking on the role of an 'obsessed' person. Obsession has a lot of negative connotations in my mind, but teasing, sensuality, and being my fiance's nympho are completely different--I love and enjoy every minute of bringing him to his knees.
How do you like to be touched? How does he like to be touched? Use what you know works, and then build upon it. When starting out, it doesn't need to be anything blatantly erotic--it could be massaging the nape of his neck, stroking his shoulders, running your hands along his spine...and if he seems to be into it, pairing that with kisses, whispering in his ears what you'd like him to do you, and what you'd love to do to him. From there (assuming you're both in the mood) it's an easy segue into more physical foreplay, and onto the main event.
The wonderful thing about that is it gives you a chance to seduce him (not just initiate sex). There doesn't need to be any end goal aside from mutual pleasure. If it seems there are times when he's less than receptive, just remember there may be times when neither of you are in the mood for full-on sex. Intimacy & sex is amazingly fun if you and your lover are open to having a good time, and taking the lead can be addictively enjoyable. My fiance is never in doubt when I want him, I love to tease, and I love being with him, seducing him, and making love with him--it's fun to drive him wild.
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