Yuugo Tani

Tani Yuugo (谷 優牛 Tani Yūgo), also known as Brute Leo (獣闘士ブルート ｢獅レ子オ｣ Burūto Reo), is a Therianthrope in service to Mitsukado Zaibatsu.

Yuugo has the appearance of a young and attractive man with short brown hair and amber eyes (however, when he experiences strong emotions such as anger or excitement, his eyes take on a bright red color).

He is tall and muscular, and his body size changes dramatically when he transforms and takes on his werelion / Therianthrope form (his muscles and height double).

(Source: Wiki)