I'm pretty sure it's canon now that Tokio believes in fate and the universe so I think it'd be funny if someone turned that into a Tokigou fic idea.
Like even something super canon compliant that's basically Tokio's pov on all the times he's seen Gou throughout the series and how as they move onto their next adventure it must've been fate that they met three times in places they didn't think they'd meet (their first meeting, their reunion and then during project mew) and how he thinks they're destined to be friends or more.
I don't know, but that line about him being a romanticist just got me thinking. Fate and the universe, unexpected meetings or reunions with the people you care about time after time, the way the world can be like a puzzle and two connecting pieces may be seperated but they'll always be brought together again. That's some Tokigou stuff.
I'd love to see some Tokigou fics based around Tokio and his romanticised viewpoint on the world and the universe.