I agree. I know (for now) it seems OOC for Oro to be sinister at all in Boruto, but just based off of his past, it'd be a waste of a character if he didn't retain some of his darkness. I JUST got around to watching the anime, and that chakra snake seems like something he'd do. Not only was it a snake form, but it had purple chakra. Oro and Sasuke are the only ones I've noticed in having chakra that color. I'm going to guess something happens to Denki after the academy/genin days are up, and he begins to believe that the shinobi world is obsolete and everything needs to be changed, but as long as Naruto is around and in power and others follow his footsteps; it won't change. So, Denki searches for more power to overtake Naruto and Sasuke and Oro is there waiting with open arms. Sorry for the ramble!