Yep, just opened it with the key. The nice shiny new key that only fits the top trunk as the PO locked his bike keys in the trunk by putting it in his glove and shutting the lid

I have the Honda hand book and that doesn't mention what its for
For what it's worth, if your ignition key will slip into that trunk lock (meaning the offsets are the same orientation), a good locksmith can rekey it so one key will do both.