Should a 21 year old date a recently divorced 27 year old?

I met this guy on campus, and he had asked for my number and we went out. I had fun but he kept mentioning his ex-wife, and they had filed for divorce in August. He also said she was his best friend, and that it was the worst thing he could’ve ever done- because there was no romantic feelings between them. He’s a really sweet, and eccentric guy but obviously if he keeps mentioning her hes not fully over her. Plus he’s 27 and I’m 21, I don’t want to become his “Play thing” because he lost all self-esteem from his divorce.