This is a relationship menu that several people can fill out, and afterwards, only the overlap is shown.
None of the data is transferred to any server, it stays right in the browser in the one device that you are using (so fill it out one after the other on the same device.)
Also, use this as a tool with nice people to figure out what you both want to talk about - if someone is malicious, they can just answer yes to everything, and therefore will see your answers, and there is no obvious way to prevent this behavior - except to not use this tool with people who are trying to screw you over. ;)
(Based on the Relationship Anarchy Smorgasboard by @adrawnnovel, original by Lyrica Lawrence & Heather Orr, iterated on by Maxx Hill, Phoenyx, & Melissa A. Fabello, PhD)