Carl was obsessed with you, like crazy. But you was dating Ron. Ron and Carl did get along till Rick killed rons dad.

Carl hated the fact he couldn't have you. So when Ron and him had a fight, he killed him, but he covered it up. He didn't want you to know he killed Ron.

"Sorry about your boyfriend." He said to you. You just nodded, grateful for an apology.

"all those muscles didn't help much." He muttered as he walked out, smiling as now he can have you.