Ken Shimizu, also known as Shimiken, is probably one of the most popular male actors in the adult film industry in Japan. While there is still a stigma for the adult business in his homeland, apparently little-known Korean publisher Ulu Games deem him famous enough to appoint him as the spokesperson for its upcoming mobile MMORPG, Arka. Another factor is said to be his own Youtube channel having many Korean subscribers. Shimiken was also known to give interviews to mainstream publications such as GQ, and famously said that there were not enough male actors in the Japanese adult film industry. Interesting choice!
With that said, I have not personally heard of Arka until recently, and it seems to be a well-developed mobile MMORPG judging from the gameplay footage. The most striking feature is no doubt aerial combat with Aion-like wings attached to characters. This is not Icarus M by the way, which has fallen off the radar in Korea after a less-than-stellar local launch. If Arka launches successfully this May, Shimiken has promised to meet fans in South Korea.