Omori Terumitsu, first called Mitsuzo, was the metalwork artist who carried the Omori line of , a branch of the Yokoya school, through the late period. Three of the four published records make him the fifth son of Teruhide, whom they call the famous master of the house. They say he took his father's common name Kisoji and inherited the headship even though there were elder sons, Hidenaga among them. Two of those records add, with a hedge, that he is thought to have succeeded as the sixth head after the death of the fifth, Hidenaga. The fourth record, the oldest of the group, gives a different father: it names him the fifth son of Eisho, the founder of the line. The published sources therefore disagree on which Omori head was his father, and the majority reading is Teruhide.
All four records open on the same judgment of his place in the house. While keeping to the carving method of his forebears, they write, he accepted the changes of his time, devised refinements, and led the line to prosperity. His materials are those of the Omori workshop: and finished in , and on one pair of guards an iron plate finished in . On these he works in and high relief, with applied inlay and colour-metal in gold, silver, and .
His subjects are the repertoire of the house rather than personal inventions. The Omori lion comes first. On a dai-sho pair of the lion is set large across the plate, full of power, and the published sources find in its face and its heavy-boned, solid body the marks of the Omori lion. On both guards the shows the lion running and the shows it seated, so that each pair of faces sets movement against stillness. A of the minogame carries the breaking waves the line is known for. The writes that the waves on the and are carved at ease and with great freedom, as though the sound of the surf could be heard, and that the high-relief inlay and the minogame are full of life, with a taut, dignified vigour in their many expressions.
The question of his signature is particular to him. His pupil Mitsutatsu sometimes carved works that went out under the master's name, and the published sources read a Terumitsu in part by the form of its . On the minogame set the shows the work to be Terumitsu's own, and the record calls it one of his masterpieces. A of the treasure ship with the Seven Gods of Fortune, a crane and tortoise amid waves on its reverse, reads the other way. It is signed Terumitsu, yet the judges it a proxy work by Mitsutatsu: the characters for Omori Mitsu match Mitsutatsu's own signature, and the is shaped to suggest the character tatsu. The record still places it level with the master's own hand, workmanship in no way inferior to Terumitsu's, and calls it a masterpiece bearing the master's .
The latest of the four records adds a documentary link to the painters of his day. A dai-sho pair of white herons on iron in , worked in high relief with gold inlay and silver , is signed with the painter's credit Kano Tohaku Yoshinobu ga before the Terumitsu , for the design follows an under-drawing by that Kano painter. The values the pair as evidence of his contact with the painters of the time. It notes the bold placing of the herons on the fine, moist iron, the varied carving that gives a rich range of expression, and calls the pair outstanding among his works.
Terumitsu's designated record is four works, all at the rank: two dai-sho pairs of , a single and a . All are signed, though one of the four is the the gives to Mitsutatsu's hand. There are no pieces, and no current holder or old provenance is recorded against them. With so small a designated record, his work reaches a collector only rarely, and the published sources show that a Terumitsu signature is weighed together with its : a lion, wave or figure subject in the house manner whose marks his own hand is the form in which his art is most securely known.