In spite of one failed assassination attempt, life carries on as normal (for the most part, anyhow) for the members of the Black Class, with tests occupied much of their time and thoughts and the only distraction coming from stories of the school's mythical "wonders", which duly fascinate Haru.
Of course, an attempted assassination is never far away, and this time around it's Kouko Kaminaga who is sharpening her proverbial (and literal, most likely) knives with a view towards offing Ichinose. However, although she's clearly a highly intelligent girl who is an intricate thinker and planner beyond compare, Kaminaga's practical skills aren't up to snuff - a problem that she dwells upon but is determined to surpass as she leaves a note of her intentions for Haru as per the "game's" rules.
With one attempt involving explosives in the refrigerator quickly put paid to by Tokaku's keen eye, it's to those aforementioned school myths that Kouko turns for her next trap, planting explosives in the school's library to match up with a story about a secret book that can bring happiness if checked out of the establishment. Of course, all this book really brings is an almighty explosion, and it's once again up to Azuma to save her roommate and foil Kaminaga's plan, which ironically also thwarts her desire to be rewarded by bringing an end to her work as an assassin.
What is effectively its episodic setup at this point is simple, but broadly speaking it still works in Riddle Story of Devil's favour - I was perhaps expecting for some more grandiose assassination attempts, but there's still something oddly compelling about watching crazy people trying to get along while also competing to kill someone. None of its characters are deep in any real shape or form, but that doesn't matter when the show clearly has more basic fish to fry, and although it clearly isn't going to match the insanity of the likes of Mirai Nikki its still more entertaining than it perhaps has any right to be.