エイは育ち、僕はプロポーズに鉄を曲げる (Ei wa Sodachi, Boku wa Propose ni Tetsu o Mageru)

Via Stingrays, My Proposal Bends Iron is a song sung by Yuuma Himemi. It is the two-hundred-and-thirty-first track in Other Vocaloid Songs 78: Over 20 New Vocaloids.