Just look who's the main upvoter on his comments. mana.bank. Sounds familiar? It should! It's a well-known voting circle, or whatever you name it. See for example this comment: https://steemit.com/cn/@mana.bank/pzebb0 - at the time of me writing this, every single upvoter on that comment belongs to that collusive voting group. There's many more of them, some have pretty high SP values, they always upvote any crap from specific accounts, and always upvote in groups. I'm pretty surprised that here we see only the mana.bank and not more of them.