Disappearing penis
Of course, fun and laughing are necessary parts of exciting and arousing sex. They help us to relax into the experience, shrug off nervousness or inhibitions and have a great time.

Now, hypnosis can certainly make sex more exciting and satisfying just on its own. It can also make it fun too.

There's the Disappearing Penis trick, where your partner thinks their best friend has mysteriously disappeared. Variations are the Disappearing Breasts trick or the Disappearing Clitoris trick.

Or your partner may find they have a sudden and uncontrollable urge to sing a marching song on penetration.

There's a whole range of things you can do and it's just limited by your imagination.
Drunk
Hypno-inebriated

Particularly if your partner is a teetotaler, and even if they're not, it can be fun to hypnotise them and tell them that they're drunk.

The big advantanges of being hypnotically drunk are that you, as the hypnotist, can turn it on and off whenever you want; you control how drunk they are; because they're not really drunk they can still respond fully and sexually (i.e. there are no problems getting an erection); and they don't wake up with a hangover.
Remote-controlled man

Using post-hypnotic suggestions you can program your partner so that it's just like having them on a remote control. You can even use a real remote control!