Well, honestly I would stay away from him if he's still on and off with your friend. If he's still her 'kind of' boyfriend then they are still technically commited to one another, and they need to chance to see if things will work out between them without the temptation of other girls and guys getting in the way.
If you really like him, try and be willing to wait it out. If things don't work out with him and your friend, then you had every right to pursue a relationship with him. But if you try to create something with him while maybe your friend is interested in fixing things with him, then she might end up blaming you if things don't work out. To the point, he needs to make up his mind before you or she really gets anymore attatched to him. :) Don't make someone your priority while allowing yourself to be thier option.
Here is a great way to find out if any relationship will last. Does he or she like to do the things the other does, and vis-versa. And are they creative enough when things get boring to do something else that will keep their interest. One of the biggest reasons why relationships go sourer is they don't recreate the relationship when times get dull. It's not knowing what to do that creates the problems. They go outside the box to find interest rather then recreate within the box. And another way to judge a relationship is how does one solve their first problem. The way they handle it is the way all problems will be solve from there on.
Avoid him all together...it is just going to cause problems between you and your friend. Friends are forever, but boys come and go and I promise if you dated him and then broke up you would still be friendless and it would hurt a lot more. I think if she is your real friend you will tell her he is trying to date you behind her back and find a different guy to date other than your friends ex. If they are on and off you never know when he is going to go back to her, why would you want to date a guy who can't make up his mind? I'm sure you have plenty of other guys you can date, don't waste your time you are better than that!
well he needs to make up his mind on who he likes more,and if its you then you have to consider your friendship with your friend, you need to talk 2 them and explain that you like her ex and see if she's okay with it if you ever asked him out. if shes not its really up to you whats more important your friend or the boy. if he choose's her then i guess you'll have to get over him. in my opinion boys are not worth it, if this boy has been on and off with your friend he sounds like he's just a heartbreaker and you could just end up getting hurt. my advice to you and your friend is there's plenty more fish in the sea :)
maybe ask him which one of you two he likes more. if its her, then youll probably just have to wait longer or get over him, if its you you could try getting with him but be aware that your freind might not like it and it could ruin your freinship, so it might be good to talk to her first and how she'd feel about it. though she also has to understand that you cant really help who you like
whut you should do is move on to the next one how do you knoe if he has more feelings for her than you you should stop wasting yer time on him nd go find some one better that only has feelings for you :)
I think that you should relax and ask him out it should be easy especially if its your best friends ex.
dnt mess wit him.... tht wud b so dirty messin wit ur friends ex...jus leave him alone
if a guy ruins a friendship its not a very good friend ship