Happy Cappy,
I don't make some judgements that some people have a tendency to do.
Your friend has an incredible concentration in Sag - Mars, Neptune, N. Node, Mercury, Sun , Venus (and Vulcan). Your Mercury and Jupiter are conjunct the concentration - and that is why you are attracted to him. Now, Pluto over the next 5 to 6 years will be conjuncting from Neptune on in his chart, and he will be in for an intense transformational process.
You have Moon square Saturn which means that your emotions can get bottled up and then explode, and since your Moon is Square his Moon and opposite your Saturn, both of you will have to learn to not to bottle up how you feel about each other - his Neptune is conjunct your Moon which will be of great help as also his Jupiter conjunct your Venus.
In short, it is a very powerful relationship and if you can be gentle in expressing how you feel about each other it should be OK.
Dave