*Edit: Thanx very much to Neil Strickland for quickly explaining to us that the following cannot be realized over finite commutative $\mathbb{C}$-algebras, as I had originally asked.* I know that there is a finite tensor category (from minimal models) with the following relations that seem rather strange to me. In particular it seems now one cannot realize it as modules over a ring. Does anyone know an algebraic situation, where something similar occurs? (maybe in a derived category?). A **non-simple** unit object $\mathbb{1}$ $$0\to J\to \mathbb{1} \to Q \to 0$$ $$J\otimes Q=\{0\}$$ $$Q\otimes Q=Q$$ (for modules over a ring $R,\otimes_R$, this means $J$ is an ideal with $J^2=J$, thus $R$ often splits, see below). such that $J\otimes J$ is an extension **the-other-way-around** $$M:=J\otimes J$$ $$0\to Q\to M \to J \to 0$$ (for modules over a ring $R,\otimes_R$ the product $J\otimes J$ cannot be larger then $J$) and which acts somewhat like a **second identity** $$M\otimes M=M $$ $$M\otimes Q=\{0\}$$ $$M\otimes J= M$$ Any hints what some of these situations are called in literature are also very welcome. Thanx very much for your help in advance!