Aries is his SUN sign .. the only one out of 40-50 astrological factors you can find by JUST looking up the month-day of birth
Unfortunately, the ONLY thing that the Sun's Sign indicates is how he relates to himself. His need to feel whole, to feel a solid self-esteem.
Aries is the style of behaviors that produces this for him.
But it does not answer YOU question.
You need to look at his Moon sign (emotional reactions), his Venus Sign (relationship needs and behaviors), his Mars Sign (how we goes after things he wants), and his 5th House (specifically about ROMANTIC relationships).
But NOT his Sun sign.
But regardless of astrolgoo one who wants someone leaves them alone. They don't want to risk alienating them, nor losing them to some other man. It would be like seeing a $100 bill on the sidewalk and walking on by without picking it up ... "I'll pick it up later" ...
His behaviors will show you how interested he is .. and how interested he is NOT.
Understand that men chase women FOR sex. Only if they are also ready to settle down are they also looking for a relationship.
I doubt if he is waiting for anything. He is not afraid to lose you, and he already had the sex.
Anyway, MOST dating relationships end and end with pain. So only a fool dates a co-worker. Unless they are about to quit and go work somewhere else.