they collaborated for the 3rd track in Jisub's new mini album, specifically in the song "Rulers" :
they have just lately released a song : "Remember Me", a nice one id say ^^ , check it out :
on January the 30th, Takers CEO uploaded a pic with Jisub on his twitter account ^^
"attending So Ji Sub hyunim fan meeting in Japan as invited guests..."
Credit : news.sportsseoul/ Twitter