Each short rest you can kiss a willingly creature (does not need to be in the lips), healing it for 1d4 hit point. You can't heal yourself.

Level 3: Healing Kiss heals for 1d6.

Level 5: Healing Kiss heals for 1d4 plus your Charisma modifier.

Succubus blood running through their veins makes sanacubi charming, and from understanding what they are, they became wise, but as non-warriors, they aren't very much of fighters when alone.

+3 Charisma, +2 Wisdom, -1 Strength, -1 Constitution

Sanacubi mature at the same rate as humans but live centuries longer.

Angelic Succubi are about the same size as humans. Your size is Medium.

The average walk and run speed of 30 ft., but their weakened wings only allow them to fly at 15 ft. However, the flying speed is increased  to 30 ft at 4th level, and 60 ft at 9th level.

Thanks to your infernal heritage, you have superior vision in dark and dim conditions. You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can’t discern color in darkness, only shades of gray.

You have resistance to fire damage.

You can cast charm person and spare the dying once a day. When you reach 2rd level, you can cast disguise self and minor illusion, each two times a day. When you reach 9th level you can shapechange each long rest. Charisma is your spellcasting ability for these spells.

A sanacubus virginity is a powerful thing...
A virgin sanacubus, if killed, will return, but won't be able to properly use any items other than food and water, and won't be able to ever level up again. Can only resurrect once.

...and the the taking of it can bring serious rewards and consequences.
The sanacubus will have 10 additional max Hit Points for 2 days, and the partner will be fully healed, even if it's already dead. Both will recover from any conditions, diseases and curses. One will be bound to the other, they will be instinctually attracted to one another. Their destinies will be intertwined, and the death of one will be the death of the other. However the bound can still be broken by a wish.