Fukurokuju

is an ancient summon whose exact origin goes unknown. However, it is said he is a being of immense knowledge, slightly predating the Shinju Tree. He is sometimes referred to simply as.

Background
Not much is known about Fukurokuju's background except that he flew the very same skies many shinobi ancestors would look at. Many legends of intelligent deity are stories of his exploits retold through different eyes. He has been an Old Sage, A women and a child. However, his name always remain the same. Similar to Danzo's Baku, Fuku is Koshiro's personal summon, as well as a being from legend.

During one of his flights, he decided to rest in a dense forest he was sure went uninhabited. However, he ran into a boy who made the woods his home. The boy followed the great Owl into his sacred grounds. Wanting to past time, he asked the boy for his past. Koshiro carefully explained everything. Even his horrible birthing conditions...Feeling for him, and seeing a great promise, Fuku offered to take Koshiro under his wings. Koshiro was the only other being Fuku knew who lived with Longevity and could possibly help build his immense library. And so, Fuku instilled the Acquisition of Knowledge into Koshiro and taught him his first field...Medical Ninjutsu. Now he lives as Koshiro's personal summon and awaits the day Koshiro finishes his journey.