This vendor produces the mythical Lotos Blossom. You may not want this one if you know the tale of the Lotos Eaters.
Basically, the lotos blossom that this vendor vends are addictive. Yes, it satisfies all drives and removes both diseases and toxins from whoever eats it. However, the flowers make creatures very sleepy and lower their libido. They reward the creature who eats it, so they'll keep eating it.
Makes Norns, Ettins, Grendels tired and sterile if left around in abundance. However, one flower will heal a Norn, and the libido lowering effects don't last that long.