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That’s right. Didn’t score on me last half won’t score on this half. I’m a ninja. Ninja Goalie.
— Justin · She's the Man
Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker confidently claims that nobody scored on them in the first half and nobody will in the second. The escalation into declaring themselves a ninja, then a ninja goalie, makes the swagger comically inflated. It is bravado delivered with total commitment.
Context reviewed