I don't think there are any spoilers here, but there are plot themes & events referred to vaguely.

First of all, for people who had trouble with the darker aspects of this series, well, the title should have given you a clue. This isn't a sweet tween drama - Gu Hai's feelings for Bai Luo Yin are over-the-top, obsessive, and unhealthy - like heroin is. This isn't meant to be an ideal relationship - relationships can be complicated, even toxic.

Many reviewers have said Luo Yin doesn't reciprocate Gu Hai's feelings, but he really does - it's just that his expressions of love are subtle. When Gu Hai asks him if he likes him, he says "you already know the answer, so why ask?" Plus, Luo Yin invited him to live with him and sleep in the same bed, so that's another hint.

- Loved the cast. Timmy Xu who plays Bai Luo Yin is so beautiful it's painful to look at him. The acting is very solid.

- The writing is unusual, as it skips the saccharine quality of a lot of BL and actually gets a tad dark - you'll know what I mean when you see it. It's played for humor, and the Chinese title of the series is "addictive", so it does make sense, but some people will not find any of it funny. The power imbalance was kind of hot, to me at least.

- Although both boys have (semi- and ex-) girlfriends, this isn't the major and consuming obstacle to the main pairing like it is in many of the earlier BLs. Here, the girlfriends here mostly serve to help the mains figure our their sexuality, and they both fit into the addiction theme.

- While you have to wait for it, there are a couple of hot consensual love scenes, at least in the uncensored version. One of the characters is way more aggressive than the other, and in a couple of cases semi-forces the other, although never for anything more than a hand-job . In one scene the more passive one was clearly parading himself in an effort to drive the other crazy, but "he was asking for it" is a bit cringe-inducing even if it's two guys.

- If there's a flaw, there is some repetition, (although common to most serial dramas), especially rejection of physical intimacy. It later turns out there is some fear of pain involved, but hand and blow jobs don't hurt. Also, the main actors are clearly way too old for high school, although I'm not complaining about that.

Ironically, the censored version is more transgressive than the full version - there are physical scenes where cutting out just as it's starting makes it look like one raped the other whereas in the full version you can see that they didn't even have sex.