Ainz proposes a group activity during the class field trip to the beach, and Aqua immediately raises her hand in opposition…until she learns the idea was actually Emilia’s, in the interest of the various class members getting along better.
Aqua has definitely been the most antagonistic towards another character—in this case, the undead Ainz—but when Subaru talks about the purpose of a test of courage, joins Ram in castigating him. Still, everyone agrees that the night activity will indeed be a test of courage; Emilia just needs Subaru to tell her what it is!
The students also need to head to a department store to buy swimsuits. You’d think that would mean they’d actually try them on, which would in some cases show many of the characters wearing different outfits—a rare occurrence to be sure. That doesn’t happen this week, as don’t yet make it to the beach.
Instead, Albedo and Shalltear try to pick out the best skimpy Speedo for Ainz-sama, and when Aqua crosses paths with them again, Kazuma plays peacemaker. He wigs out when he learns Albedo is a succubus (based on his experience in his isekai) but Shalltear drags her fellow floor guardian by telling him she’s still a pure maiden and laughing about it.
For that, Aqua actually takes Albedo’s side; saving yourself for the one you love isn’t anything to be ashamed of. Instead, she inadvertently drags Shalltear by declaring the only thing to be ashamed of is padding your chest, as her fellow goddess Eris—and Shalltear—do. A such, it is Albedo who gets the last laugh.