Artist, programmer, and composer behind Trick Nostalgie, creator of the Len'En series of games. They're also known for having made remakes of stages from the PC-98 Touhou games, shown only as teasers on Niconico, never to be released to the public.
They've also created their own pair of "VTuber Androids", Rei (Len'En) and Zelo (Len'En), who also seem to be characters in the Len'en series, even having their own Twitter account. Alongside them, Jynx also has their own VTuber avatar, Tabinoki Kanae, that's independent from Len'en.