Silk Hiding Steel: A weird case. While she makes a good commanding officer, she's really unused to actual action.
Status Quo Is God: Played for laugh in Kishin Hishou. Turns out that her parents are such lovely couple who go on honeymoon for most of the year, so Ruri still has to handle all business even if they're alive.
Bunny-Ears Lawyer: Although Anticross finds his methods questionable, there's no questioning his sheer magical power. Then again, they still kill him off anyways, rejecting his plan to destroy the world.
Disc One Final Boss: In the first game, he's the mastermind behind all the chaos, but Master Therion himself is a pawn in Nya's scheme, and Nya is the real Big Bad of the whole epic.
Dissonant Serenity: His expressiveness rarely goes beyond boredom or some sort of vague entertainment.
Eleventh Hour Ranger: Master Therion is the most powerful secret character in Super Robot Wars UX, so he joins your team before the final scenario. He has the best default stat in the game (higher than Kurou) as well as the same skill set as when he was the enemy.. The Liber Legis also has a default S rank in every terrain too. Its bonus is +300 attack power for both Melee and range weapons, has an immunity to status change and a 35% special evasion. And the most important thing is that he has the "Tamashii(Spirit)" Seishin.
Evil Counterpart: To Kurou, which is lampshaded quite a few times in the story itself.
Lack of Empathy: Oh, yes. He makes his entrance by shoving Leica aside with enough force to knock her unconscious... and then apologizes and says he can't be bothered to look at insects while he walks.
Bunny-Ears Lawyer: Behind all his quirks, the man is a pure genius. He built a fully sentient Robot Girl and the fact that his mechs can even stand up to Demonbane despite being 100% science and not Magitek (outside of Demonpain) is really impressive.
Eye Scream: Gets an eye taken out by Kurou during their first battle.
Moral Myopia: See Claudius' entry. Caligula sees nothing wrong with causing lots of collateral damage, not giving a damn about the people he kills. However, Claudius is a friend and must not be harmed.
Actor Allusion: In Super Robot Wars UX, Aoi punches Augustus with Absolute Nova Beast for a finish, like she punched Moon Will in the Dancouga Nova anime. Moon Will and Augustus are voiced by Norio Wakamoto. Also serves as a double Mythology Gag of characters voiced by Norio Wakamoto being punched as they are defeated, and Wakamoto characters being defeated by people from Dancouga (since he also voiced Shapiro Keats in the original series).
Stone Wall: His robot, the Legacy Of Gold, is definitely one. It is protected by an extremely powerful forcefield and by an extremely thick armor, and even if an attack gets past all of that, the Legacy Of Gold has huge regenerative powers that can negate all damage in a few seconds.
Thanatos Gambit: She's the one destined to give birth to Master Therion, as one of the final pieces in Nyarlathotep's plans. To throw a wrench into them, she tries to force Kurou into killing her. However, Kurou manages to disable her Deus Machina, the Nameless One, without killing her.
Hoist By Her Own Petard: Too bad for her, she didn't expect Kurou to be able to combine the power of two Shining Trapezohedra into a single Laser Blade BFS and use it to effectively make her own plan negate itself.
Louis Cypher: Anyone even vaguely familiar with the Mythos can see where this is going.