He canonically has a wife and one daughter, but the creator has said he sees Ronin as having two daughters and an ex wife so decide what you consider cannon lol
Ronin was the one who gave Zane and Pixal to Chen but he didn't want to. Originally, he was hired to go kidnap someone for a LOT of money as in enough to pay off all of his debts but when he found out who, he didn't want to do it anymore. So Clouse threatened to hurt his family if he didn't cooperate.
One night, a drunk Ronin was approached by a guy named "Sultan Archron" who offered Ronin a deal that he said would cost him no coin. Ronin agreed, not knowing at that moment that he was indebting his soul to Soul Archer. (Who was human at this time) Having made a deal with Soul Archer, Ronin knew that his soul would end up in the Cursed Realm should he not pay the Archer off on time. After the Archer was banished to the Cursed Realm himself, the deal was seemingly disintegrated. However, the ordeal left him paranoid, so he created his eyepiece to detect paranormal essence.
He was briefly seen at the Biker Tavern as Morro arrived and left before he summoned Wrayth.
Ronin has a somewhat implied relationship with Ed and Edna as in day of the departed when he shows up and saves them he nervously tries to cover up the fact that he was gonna steal some scraps and Ed just laughs and gives him some telling him to just ask next time
Prior to Sons of Garmadon, At one point Ronin was hired by Kai and Zane to take them to the Tomb of the First Spinjitzu Master in their search for Wu
In an effort to clear his name during the same time, Ronin made a deal with the Police Commissioner to run a "School for Crooks," a criminal reform course partially designed to counter the rising threat of a new criminal gang reported to be recruiting members. (AKA sons of Garmadon lol
Ronin hangs out at Dareths bar
That's all I got!