Vendy will give you a Vox Recorder if you can prove love is true by engaging in conversation with them in a way that satisfies their romantic nature. You can safely try various routes through dialogue, without accessing these hints, if you like.
This is the low-spoiler guide for "Proving Love is true." puzzle in Henry Mosse and the Wormhole Conspiracy. Unlike in normal walkthrough, you get gradual hints on how to solve the puzzle. Click the big button below to see your first hint. If the hint contains a spoiler, you will be warned about it before clicking.