Big Sean wonders "
This singer claims "I'd wait for you forever and a day" and "your world is my world" in one song. Big Sean wonders "I don't know if this makes sense, but you're my hallelujah" in a song where this singer says he'll be your (*) platinum, silver and gold. In another song, this singer says "you'll never be alone" and "I can be a gentleman" if he was the title figure. For 10 points, name this singer of "As Long As You Love Me" and "Boyfriend."
This singer claims "I'd wait for you forever and a day" and "your world is my world" in one song.
Justin Bieber