His last name sounds like "10 inch", which is likely a reference to the size of a penis.
He can also be found in the Algonquin most wanted list under the name Christov Mahonvic. Mahonvic is a Russian born criminal who worked for both Vlad Glebov and Mikhail Faustin. Although it is possible to kill him during both encounters, he somehow survives and he continues his criminal lifestyle up to the point where he is wanted by the L.C.P.D.
It is possible that Tenninch is Mahonvic's secret idenity.