He can't lose what credibility he doesn't have, though.

There's a small lean back from the detective, followed by a raised eyebrow. "Not that the present isn't important, but past experiences and memories make us who we are!" The question that comes after, however, gives Shoutarou pause. He strokes his chin for a moment, then his shoulders droop. "...I can't say I know. You left before we could exchange names."