Reddit mentions of M-D Building Products 02097 2097 M-D 0 Low Density Open Cell Self-Adhesive Foam Tape, 17 Ft L X 1/2 in W 3/8 in T, Gray, x H x 17' L

Your best bet would be to buy one of those two fan window fans off of Amazon and seal it relatively well in your window. As long as the fans are on air will always be pulled into your room from outside your door so there will never be any risk of smoke leaving your room. You can always test the airflow by holding a lighter up to the gaps in the doorway/window. If just have a normal window fan pointing out the window usually a lot of air still enters the room and just defeats the purpose of the fan. If you can't open your windows in the winter you can always buy some foam window/door sealant to stick around your door frame to create a perfect seal. As for the sploof, tape some dryer sheets around the end of the toilet paper roll, then dump in about an inch layer of activated carbon, then stuff some more dryer sheets on top just to keep the carbon in. This sploof will completely eliminate ANY odors in the smoke making it smell like absolutely nothing. If you ever get tired of using the candle to light your bowls you could try out some hemp string. The main thing you'll have to worry about it letting the weed in your bowl burn freely. Make sure to put it out right away, only pack enough for one hit, or have something ready to cover the bowl with :D

Read my mind. I was going to suggest something like this, but now I'm thinking it could be a stickiness hazard.