Professional sumo wrestler Kaloyan Mahlyanov, aka Kotooshu, is officially no longer Bulgarian.

On Sunday, Kotooshu, 30, became Japanese citizen, which paves the way for him to become the country's national sumo coach after the end of his career as competitor.

In November 2013, he applied to be released from Bulgarian citizenship and adopted the family name of his Japanese wife, Ando.

Some time ago, Mahlyanov explained that in order to become coach, he needed Japanese citizenship and license. He has the chance to become the first European sumo coach in Japan.

Mahlyanov has said on numerous occasions that he saw Japan as his second homeland and planned to live and work there.

From November 2005 until the very end of 2013, Kotooshu was holding the highest ozeki rank in sumo.

He is the first European to win the Emperor's Cup in May, 2008.