Triangle Noesis (三角座（トライアングル）のノエシス, Toraianguru no Noeshisu) is one of Silver Saints.
A noble Silver Saint. He is killed shortly after his introduction, when he and his apprentice Retsu are fighting against the gorgon Euryale. After having half of his body turned into stone, he uses his attack, Tritos Spharaghisma, making the gorgon unable to petrify Retsu. But this causes the rest of his body to turn into stone, and is accidentally blown the top part off. Later, he joins his Cosmo with Retsu's, and with the last remains of his soul, they defeat the gorgon.
- Tritos Spharagisma (三界封印（トリトス・スプラギスマ, Toritosu Supuragisuma, lit. Seal of past, present and future)