@feha it's weighted Runs Created plus. It's a combined measure of how well a player performs in a variety of offensive measures expressed on a standardized scale where 100 is the league average performance and each point above or below represents one percentage point deviation from that mark.
120 would be a player who is 20% better than the average mark. By MLB standards that would make a player pretty good. around 140 or so is about where star players start popping up. I don't know the scale might be different in Japanese baseball given how differently players of that league perform (more hits, less walks, less home runs)
https://library.fangraphs.com/offense/wrc/