I didn't think he would die for the mere fact he's the MC. But when his hand got chopped off I was like "Wait, will he fight later with only one arm..." and then his leg got bitten off and I thought "Waaaaaaait, how is he supposed to fight later?!" and I was very confused
Though I can't remember if I really thought he's dead, there was still this confusion. And when that one titan appeared I immediately thought "Wow, did Eren take control of the titan that ate him?!", well, wasn't too far off I guess