Gen blushed even more, though. Tracking Senku down once he realized the connection between this guy Tsukasa supposedly killed and the writing on the tree. Getting the observatory made for Senku and trying to get him things that'd be useful, like the microscope most recently. Tapping little messages in morse and telling him about everyone on the ship who seemed suspicious.

He really hoped that Senku didn't realize Gen kind of met all of those criteria.

"It's a really good thing you're married to your science, my dear," Gen said brightly, still ignoring his blush, Senku was ignoring it, so it was totally working. "Science will never complain about how sappy you are when you write it a love letter of these constellations across this train car."