Summary

This device is a little special effects fogger to be used to blow bubbles with some fog inside.

The design is intended to:
A) make a reliable, small, portable, low-cost fog maker,
B) not have to inhale the special effect fog directly,
C) use this device around children and hide the fact that the internal mechanism is actually a vape pen. (In fact, I don't even want it to appear as though I'm smoking.)

The core component is a Tornado vape pipe from Totally Wicked.
https://www.totallywicked-eliquid.com/tornado-v5-usb-e-cig-kit-and-e-liquid
You can buy vape juice with no nicotine. But I suggest that you simply purchase some vegetable glycerin and mix it with water. About 70% glycerin 30% distilled water seems like a typical mix.

Assembly requires a 6mm straw and two 14mm O-Rings.
https://www.grainger.com/product/FABORY-Round-Medium-Hard-Buna-N-O-41KV82
Getting the O-Rings into the slot inside the tube is a bit of a chore. I managed to convince them to stay in the slots with a small screwdriver and a bent paperclip. It took about five minutes.

The straw will need to be cut in half with each piece inserted partway into the holes at the top.

This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/fdWlJq1B054

The 25mm diameter Bubble Pipe was designed for a request. I've not tested it not do I know if it fits any vape pen properly. It can be edited and found here:
https://www.tinkercad.com/things/fdWlJq1B054-bubble-pipe-25-mm-diameter