New Adventures of the Tattoo Girl

This is one of  the tattoo girls tattoos

I’m having a problem, as of recent dealing with something.

My tattoo girl has ended her relationship with the guy she was engaged to. They were together for two years. Even though they had not set a date, they planned on getting married after they finished college.(smart move in my mind)

Which I guess is a good thing now. I'm not a 100% sure as to why she broke it off with him. but I have a good idea.

I think he is a nice guy and I know hes very sad right now.

but I have told my tattoo girl early on, don’t settle down at such a young age.  There is sooooooo much out there in the world to see.
and its harder to do if/once your tied down.

Meanwhile the tattoo girl has met someone new. Which is fine.
You can never have enough friends. I always say.

However, I think my tattoo girl likes this guy enough to wanna date him. 

I don’t have a problem with the tattoo girl dating.
Not at all. She is old enough.
I dont expect her to be alone forever.  Dating is good.

What I am not so sure about is………………………..

The guy she met and is sorta seeing is someone who is 1) in a freakin band, 2) is 9 years older.

Um, I’m not sure which I find worse.  I’m not happy with either.
The only good part is that he is a “straight Edge” kinda guy.

Now the tattoo girl is a very responsible person for her age.
More responsible than a lot of adults I know.

I also know that if I make a big deal about it that she more than likely pursue him out of spite. (weve been down this road before and I have learned my lesson with butting in)

So, what do I do?
 What are your thoughts. 
 Should I leave it alone?
Wait it out?
Or
should I tell her how I feel?
We are very close now that shes older and not in HS anymore.
or
Should I have my brother run his info and see if he has any deep dark secrets?

Shame on me, but I have already googled him to see what I can find out.

Looking for some suggestions please.