User blog comment:Piyush Banerjee/Shin DxD 2 discussion/@comment-2605:E000:3E1A:4700:8DE1:BE76:9DDD:76D0-20190602092526/@comment-83.49.75.237-20190602115204

Rias needs 3 pieces too. BISHOP, KNIGHT and ROOK. However, these 2 are not warriors..

The same happens with his parents, they will die in less than 50 years. Issei should accept that he will lose his parents and humans friends someday. They don´t have the devils long lifetime.