Back from the Dead: He can be miraculously brought back to life by the powers of Leknaat's Gate Rune and the 108 Stars of Destiny if all other 107 Stars are recruited and are still alive prior to the final battle in Gregminster.
Undying Loyalty: Utterly devoted to the young master. It can become literal near the end of the game, as Leknaat can use the Gate Rune to bring him back to life if you have gathered all of the 108 Stars of Destiny.
Big Eater: He often complains he's hungry in the early part of the game.
Bodyguard Betrayal: He informs the Imperials that Ted possess the Soul Eater rune, starting a chain of events that leads the hero to join the Liberation Army. However, he will get himself redeemed later on in the game.
Defeat Means Friendship: He was defeated by Teo McDohl in hand-to-hand combat and since then has served under him, almost as a live-in servant/bodyguard.
Gotta Catch 'Em All: He's pretty tough to recruit, as he must be of a sufficiently high experience level to best Teo and therefore become available.
Sibling Yin-Yang: He is a strategist who was formerly a pacifistic teacher, who was formerly a master strategist in the Imperial Army; whereas his sister Odessa is a rebellious girl and early on in the game, leads the Liberation Army.
Celibate Hero: He always says he "has somebody" (refering to Odessa) as a rebuttal to female advances.
Cool Sword/I Call It Vera: He named it after Odessa. This and later, as noted in Hix's entry, is a hint at the origins of a number of very dedicated men. Any man in the main series whose weapon is named in pattern of Loved One's Name and a '+' was a man who was raised in the Warrior's Village.
Sour Supporter: Initially despises the Hero due to Odessa's death. Once he calms down, he agrees to help him out, but still refuses to acknowledge him as the leader. It isn't until Gremio's death that he finally warms up to him and offers his full support.
Henpecked Husband: There are rumors that he's not the real power behind Toran Republic, but rather Eileen, because Lepant just can't refuse her. The good thing is, Eileen is a very kind, non-abusive woman.
It's Not You, It's My Enemies: He tried divorcing Eileen to keep her away from the inherent dangers of joining the Liberation Army. Eileen insists on coming along anyway, and again, Lepant can't say no.
Inexplicably Identical Individuals: Like Jeane, she turns up in every single Suikoden game, regardless of space/time differences. Unlike Jeane, however, this is explained by her powers of teleportation.
Mysterious Past: No one really knows where she came from. It's unclear whether even she knows.
Warp Whistle: Her speciality. As bearer of the Blinking Rune, she can (most of the time, see below) transport the hero and his party to any destination previously visited.
Teleporter Accident: Her abilities can be hit or miss, occasionally landing the characters in completely random locations. Consider yourself lucky that's all that happens; the other games of the series demonstrate that she can also end up teleporting to completely random times.
Only Sane Man: Amongst the Toran elves. Kirkis is notable by being the chronologically first non-prejudiced elf that came to power and probably changed how Elves treat themselves and others through the rest of the timeline.
The Fighting Narcissist: Along with fellow Narcissists Milich and Esmeralda. Contrary to the trope however, Vincent isn't available as a party member, but when he reappears in II, he can fight.
Flower Motifs: Specifically roses. He has them on the back of his cape.
I Owe You My Life: He was freed during the Liberation Army's rescue attempt on Moravia Castle (except you have to go back to actually recruit him), and proclaims eternal gratitude, vowing to aid the hero by joining the Liberation Army.
Impoverished Patrician: When first encountered, he's involved in a dispute with a local proprietor, trying to dodge paying a bill, stating that "it was the man's honor to have Vincent De Boule dine at your establishment".
Armor Is Useless: Subverted. He's pretty easy to defeat, despite being encased in armor. Once he joins you, however, he can equip the heaviest armor available and he becomes the defining Stone Wall of the team.
Revenge: Wanted to avenge Teo's death at the hero's hands.
Sour Supporter: She agrees to join the Liberation Army so she can see the hero die in combat.
Wicked Stepmother: To the hero. She and Teo were lovers before the war and she is extremely hostile toward the hero for killing him. She eventually forgives him, however, upon realizing how futile her efforts for revenge are and noticing how much Tir has grown to resemble Teo
Redemption Demotion: Once he's recruited, he only uses throwing darts for normal attacks, not like the Flash Step close combat attacks displayed when he fought you. He'll still use it when he goes Unite Attack with Varkas, though.
Rescue Arc: Early on, the hero must rescue him and Varkas from Rockland's military commander, Grady.
The Runaway: Taken in by Varkas after he ran away from his cruel tormentors at the circus when still a child.
Hostage Situation: He was abducted by Milich Oppenheimer to draw his portraits for him.
And Your Reward Is Paint: The random pots of paint discovered throughout the world map are all required for him to complete his mural.
Alchemy: His speciality. He had used his alchemical powers to develop an engine to burn oil to produce motion, when the hero recruits him to help build a ship that can traverse the Dunan Rapids to reach Liukan's hermitage.
Nice Hat: Tall, conical and similar to a nightcap.
Shout-Out: Named after Casio, noted makers of electronic keyboards.
Stockholm Syndrome: It's unclear, but he appears to be imprisoned at Scarleticia (in a similar manner to Ivanov) purely to play music for Milich. However, he appears to care for him very much and is perfectly happy.
What Kind of Lame Power Is Heart, Anyway?: He's surprised when offered a position in the Liberation Army, commenting on how the hero is a "weird guy to recruit someone who only knows how to cut off heads".
Bag of Sharing: His speciality. He looks after the HQ warehouse, where all items and equipment can be dropped off, stored and retrieved when necessary.
Villain Ball: After cajoling the hero into stealing Kirinji from Lepant, under the pretense that it will help to gain an audience with him, he tries to dose them all with Robber's Tea and steal the sword himself. The attempt backfires (as the heroes had fallen for it once before and knew what he was doing when he mentioned tea) and Krin is forced to drink his own drugged tea.
Furo Scene: His speciality. He has a passion for making baths, and once recruited, he builds a large onsen at castle HQ where party characters can be seen enjoying a nice soak. The onsen also serves as an area to display any antique treasures discovered.
Bathtub Bonding: Certain combinations of characters and antiques placed within the baths will activate a variety of mini scenes.
Adaptational Badass: She already had a good stat growth in-game, and is a good archer though she unfortunately died way too quick. However, there was tie-in material which revolves around Odessa and her first lover before Flik came along: Achilles. It was this man's death and his final speech of "Defeat the Empire!" which spurred Odessa to kickstart the Liberation Army... and kill a lot of Imperial soldiers with just a sword, whilst still wearing her wedding gown. And it's canon. She might've bitten the dust too early because of maternal instinct kicking in at the wrong time, but dang, she's Badass.
Chekhov's Gun: She made up plans for the Fire Spears and just asks for them to be stored in the Secret Factory so they'll come in handy. It does, when it ends up beating Teo's invincible Armored Cavalry.
Hope Springs Eternal: She is always insistent on keeping up the tiny ray of hope of defeating the Empire despite her tiny army, which spurred her long term plans. This is also why she requested that nobody tells anyone about her death, because it would kill the Liberation Army's hope and morale.
Quickly Demoted Woman: She joins the party early in the game, and has great stats - unfortunately, She is killed very soon after joining as a Plot Device to allow the Hero to take over the leadership of the Liberation Army
Sibling Yin-Yang: Mathiu is a strategist who was formerly a pacifistic teacher, whereas Odessa is a rebellious girl and early on in the game, leads the Liberation Army.
And Now for Someone Completely Different: Shares this role with Mathiu, mainly when you want to switch party members without advancing the plot (which is almost always triggered by talking to Mathiu) or if Mathiu is somehow unavailable.
The Atoner: Following his betrayal, he is pardoned by Lepant and cloistered within Qlon Temple.
Beware the Nice Ones: It's pretty shocking when it is discovered that mild-mannered and seemingly loyal Sanchez is an Imperial spy who facilitated the deaths of Mathiu and Odessa...
The Mole: He secretly infiltrates the Liberation Army as an Imperial spy and cruelly betrays Odessa, and then the Hero..
Becoming the Mask: He nearly becomes one, having grown to care for everyone in the Liberation Army. Unfortunately, as an old man, he's unable to let go of the past ways. He still felt horrible for betraying the team though, and was even willing to let Flik kill him for punishment, until Mathiu said otherwise.
Amulet of Concentrated Awesome: She is the keeper of the Gate Rune, a True Rune that has the power to open portals to other worlds and dimensions. It was split in two following an attack on her village of the Gate Rune Clan by Harmonia. She kept the back half, Windy kept the front half. It is assumed that she reclaimed the front half after Windy's death.
Back from the Dead: If all 108 Stars of Destiny are recruited and kept alive, she resurrects Gremio.
Blind Seer: Her role is to provide astrological projections.
Amulet of Concentrated Awesome: She is the keeper of the Gate Rune, a True Rune that has the power to open portals to other worlds and dimensions. It was split in two following an attack on her village of the Gate Rune Clan by Harmonia. She kept the front half, Leknaat kept the back half. It is assumed Leknaat reclaimed the front half after Windy's death.
Better to Die than Be Killed: She and the Emperor dramatically leap from the palace battlements when they are finally defeated, though it isn't her choice to do so.
Manipulative Bitch: She used her magic to charm the Emperor and keep him compliant. Or so she thought. At the end of the game, he reveals his Sovereign True Rune acts as an anti-magic barrier and he does genuinely loves her.
Anti-Magic: His Sovereign Rune acts as a barrier to all forms of magic deployed against him, including Windy's charm spells.
Anti-Villain: He's actually a pretty decent guy, even letting Futch leave his gardens without a fight, and he basically comes across as a guy who let everything in his life go to pot because he couldn't handle the death of his wife.