Darker Beach

It's simple, Eun. Even though your motives are selfish, you're still offering to help, and help always deserves thanks. Because thanks can make the brain release feel-good chemicals which can be enough of a selfish motive to get people without other motives to help.

Felicity isn't that cynical, however, she's just thanking Eun for offering to help with a problem that isn't her speciality and which Felicity- who got herself in the position to need help in the first place- is struggling with. "No, Eun. You're a physicist, and you're offering help with a biochemical problem using exotic materials and substances that don't always behave as one might expect. Triffid oil at least is oil, even if it's pink." Some of the stuff she uses is stranger than an extract from a moving predatory plant.

Volleyball

"Uh, sure!" Mishnehel takes the ball and thwacks it back over the net, aiming it as close to the middle between Zefir and Vlad as she can.