It was Prashant!
In reality, Prashant came in front of Kashi at the exact time, when the gun had been shot at Kashi.
Prashant was suffering in her arms in a half-conscious state and his shirt was completely covered with blood from behind. It was more than Kashi's body mass, that's why both of them rolled down and sat on the ground.
Seeing that sight in front of Sumit, Preety & Kashi for the first time, the ground eroded under their feet, whereas, Abhay was very happy to see this and see their helplessness and sorrow while making fun of them, he started laughing. At that moment, all three of them were getting angry, especially with Sumit.
Seeing Abhay's act but they knew that better than taking out their anger on him now, they should pay attention to Prashant. Because of this while ignoring Abhay, Sumit sat down on his knees and both three of them looked at Prashant with tearful eyes. Sadness was evident on their faces.