ZTF J1406+1222 is a trinary star system consisting of a "black widow" binary and a third far-flung star that orbits the other two every 10,000 years. The very academic term "black widow" refers to one of the two stars, which is a neutron star (or a "pulsar"), that orbits another smaller star and slowly "feeds" from it, sustaining itself. Because neutron stars are violently and rapidly spewing out neutrons, they usually die out pretty quickly (in stellar terms). This one will be longer lived, because it is replenishing its mass by slowly feeding off of its partner. The term "black widow" is a reference to the black widow spider, who will paralyze and consume her mate shortly after mating (unless the male can get away!)
This is not merely what makes this system so exciting, though. This star system contains the fastest known orbit of any binary star system; these stars oscillate around each other every 62 minutes! This is probably hands down my favorite star system. They still haven't added it to Space Engine, but I look forward to the day that they do.
You can read the original paper detailing this system here. This is the spacedaily.com version of the link, which should theoretically give you viewing permission.
// Brevity Quest 2023