My friend is in a bad relationship and i'm worried

I’m posting anonymously because some people from school use this. My good friend “Nathan” has a boyfriend “Michael”. Nathan loves Michael and i’m ok with his sexuality, the reason i’m making this thread is because i’m worried for my friend. Here’s why:

- Michael lied about his age.. He said he was 21 but is actually 26. Nathan is 17 now, but 16 when they started going out. The age gap concerns me and also the fact that he lied, maybe he lied about other things too
- Michael is very unreliable. He never shows up on time, doesn't do what he said he would, is never there for nathan when he needs him
- But nathan is the complete opposite. He goes out of his way to do what michael wants him to, always puts him first and himself second
- Michael is very manipulative. One time i was hanging out with nathan when michael phoned and i overheard him saying like “oh don’t you love me anymore?” “i’m your boyfriend, am i not important enough?” when nathan was trying to say he had other plans for the weekend

This has been going on for 6+ months and i try to convince nathan that he needs to break up with michael but he keeps defending him. He says they love each other but i very much think it’s not that mutual!!
I couldn’t convince him so i gave up on the whole thing until i heard what happened last week: nathan needed to get home from a party and called michael to come pick him up. Michael did it but he asked for gas money but nathan didn’t have any on him so michael demanded a blowjob instead. Nathan didnt want to but michael apparently threatened to kick him out the car in the middle of nowhere. So Nathan did it. Nathan said it was fine because they've had sex before but i really think its not!!! There seems to be no way of convincing him otherwise though. So what shouild i do? I want to help my friend but he won’t listen, but he deserves so much better and he’s gonna get his heart broken if this keeps going any longer

Michael is a dangerous control freak who is nearly 10 years older than his 17 year old boyfriend- and lies about his age. It is hard to help someone like Nathan who does not want to help himself. I wonder whther Nathan is actually underage? You could call Childline and ask for advice. Also, Nathan should confide in a trusted mature adult so that this abusive relationship can end.

(I'm the same anon as before)

He hasn't told anyone except me and one other friend about his relationship because he thinks his parents wouldn't approve. He is underage so isnt this whole thing illegal in the first place? I thought of calling childline but nathan would be angry with me if he found out, we've already had several arguments about this whole thing. I just want him to be safe and happy but don't know how I can help