Does it actually get hot?

No. There is no combustion and no heating element — the flame is mist lit from below. The unit stays cool to the touch, which makes it safe around fabric, pets, and children in a way a candle is not.

Can I use essential oils in it?

Yes. Add a few drops of any water-soluble essential oil to the reservoir. Use oils sparingly and rinse the tank between different scents.

How realistic is the flame, honestly?

From across a room in low light it reads as real fire. Up close you can see it is mist, but the movement is organic rather than a looping animation, which is what makes it hold attention.