It's part of the advanced courses at Shipgirl Identification School.
What's that? This is porn? Psh. Maybe to some sick shipfucker. This is the vessel ID field guide. It's not erotic, it's tactical. Huh? Why am I hiding a "field guide" under my bed? Uh, well it's classified information right? A lot of people died gathering this information. We can't just let anyone see what our intelligence is. OPSEC! Yes! It's nothing to be ashamed about~