The German, who is contracted to Stamford Bridge until 2017, is on a season-long loan at Sevilla and says he has received plenty of enquires.
The 24-year-old, currently recovering from a thigh injury, said in the Bild newspaper: "As things stand now, I am supposed to (go back), but I've had so many enquiries.
"Sevilla want me to stay, but that's not a decision only they can make. I would like to stay too because I really like it here, but in the end, it's up to Chelsea what happens.
"What matters now is that I get fully fit again.
"When I am fit, then we want to reach for the top. We are within touching distance of Champions League qualification and that is our goal. We've got the quality for it."
And Marin expects to receive more comparisons with Lionel Messi when he hits top form again after injury.
He is focusing on regaining full fitness after a spell out with a torn thigh muscle, but he fully believes he will get back to his best and silence his critics.
"I'm loving it here in Spain," he added. "The club, team and the fans - everything is perfect.
"People love me in Spain. I've already been likened to Messi, and when I am really fit again then these comparisons will resurface.
"I just need two or three more weeks. Everything is really perfect here, probably better than in England, even though I did enjoy my time at Chelsea."