!Protagonist
The main character of the game's story. He got into a bet with his childhood friend Miki where he must obtain and hold onto a girlfriend within 101 days.
----
* AccidentalPervert: Among others, [[PantyShot he catches a glimpse of Tsubasa's panties when the latter trips and falls running.]]
* TheCasanova: Can get up to 8 other girls to fall for him, and late into the story, starts to gain passerby admirers.
** CasanovaWannabe: He has to work for that though, so he's this trope early on. Even more so if the player controlling him chooses more perverted dialogue options, which don't net you many points with the ladies.
* ChickMagnet: Can get up to 8 other girls to fall for him, and late into the story, starts to gain passerby admirers.
* ChildhoodFriendRomance: Can potentially form one with Miki.
* DeadpanSnarker: He's a pretty sarcastic guy, especially around Miki and Keika.
* HelloInsertNameHere
* {{Jerkass}}: Potentially, if the player controlling him chooses the more mean-spirited dialogue options. You'll have a hard time getting anybody to fall for you this way though.
* JerkWithAHeartOfGold: By default, but can be a simple {{Jerkass}} if the player so chooses.
* OrdinaryHighSchoolStudent
* PlatonicLifePartners: With Miki if you choose not to romance her.
* ShipTease: It's a dating sim, of course there's plenty.
** Miki [[TheRival (For]] [[VitriolicBestBuds obvious reasons]]) and [[{{Tsundere}} Riho]] (for lesser known reasons), appear in more story events than any other girl. The former is always known at the start of the game due to her kicking off the plot, while the latter is difficult to not meet (Doing so would require you to refuse a race with Miki early on and then fail a Mind check that comes later, if you don't refuse to attempt it entirely, and that doesn't even require your Mind stat to be that high.) Due to this, and Keika disappearing from the story until you find her at the gym, conversations with them are frequent.
* VitriolicBestBuds: With Miki.

!Riho Kaneshiro
Younger sister of school idol Shihoko, and classmate of Miki. Riho is an abrasive bookworm who feels the need to excel at everything. But as the player gets to know her, she turns out to have put more on her plate than she can handle. Will you be the shoulder for her perpetually stressed mind to lean on?
----
* AccidentalPervert: In a cruel twist of {{Irony}}, while studying with him the Protagonist at the library, she accidentally puts her hand on his crotch area trying to catch a pen rolling off the table.
* ClingyJealousGirl: If both she and her sister Shihoko fall for the Protagonist, she does ''not'' take it well. She starts by throwing her boxed lunch at Shihoko and storming off when the latter's kissing up to the Protagonist, and then later on, when Shihoko tries to take him to the girl's locker room to make out, [[spoiler:Riho drags him to the side of the school, pins him down, and pulls her shirt up in front of him to blackmail him into not going.]]
* CuteSportsClubManager: She's the manager of the boy's baseball team, but derives no enjoyment from it, since the boys on the team are constantly fighting and driving her up the wall. A major part of winning her over is lightening the load on her back. [[spoiler:In her ending, she becomes an athletic trainer.]]
* DontLookAtMe: After pulling an all-nighter working on a paper, Riho is mortified to come to school with bags under her eyes.
* FashionableAsymmetry: Her ponytail is always hanging over her right shoulder.
* GoGetterGirl: [[DeconstructedTrope Deconstructed]]. Riho signed on to be the baseball team's manager since it'd look good on her college application, spends a ludicrous amount of hours studying for every test, picks obscure and complicated topics for her essays because she thinks it will impress the teacher, and is regularly making lunches for she and her sister too. Predictably, this insane self-imposed workload leaves Riho VERY stressed out most of the time, and will only get better with the Protagonist's aid.
* MotherlySidePlait: Ties a ponytail over her shoulder, and regularly handles making lunches for herself and her sister. [[spoiler:She alludes to wanting kids in the future, too.]]
* OnceDoneNeverForgotten: The Protagonist will never let Riho live down her cheesy "Pervert Police" quip, [[spoiler:Even when they're both out of college.]]
* PermanentlyMissableContent: It's possible to never meet Riho, but since missing both events where you can meet her requires first refusing to attempt one of the first skill checks in the game, and then failing an easy Mind check later on, the player practically has to be trying to lock themselves out of her route.
* {{Tsundere}}: A refreshingly [[https://vndb.org/g194 traditional example]], actually. Riho begins the game with a vocal distaste for the Protagonist, viewing him as a creep perving on girls to win his contest with Miki. She gradually warms up to him as the game goes on, potentially even falling in love with him.
* WomenPreferStrongMen: Athletics is her favored stat, and one of the things you can do to help win her over is to play for her baseball team a bit. Getting your Athletics stat into the [=50s=] is necessary for unlocking her ending, as it's locked behind a very high check involving [[spoiler:a runaway hacker.]]
* {{Workaholic}}: Oh, dear. She studied ''20 hours'' for a single test. Small wonder she's so cranky all the time.

!Custom Characters
!!Uchioniko
!!!Terakado Shoko

* BuxomBeautyStandard: Ruri lampshades this when you ask her about Shoko.
* CharacterTics: She communicates entirely in hand gestures.
* CuteMute: She rarely talks, but opens up when you unlock her ending.
* ShrinkingViolet: So shy that she typically only communicates via hand gestures.

!!!Momotami Ruri

* GenkiGirl: She's definitely genki.

!!!Nemoto Mayu

* AllAmazonsWantHercules: In order to open up her storyline, you'll need to have fairly high athletics stats early on for two events. One in which she has you fight the gym teacher in a martial arts demonstration, and the other in which she trains with you. This actually makes it fairly difficult, because you need to train your athletics to the exclusion of everything else to accomplish this.
* {{Tomboy}}: She's most focused on athletics, and the short hairstyle completes the look.

!!!Shirazu Izumi

* [[spoiler:IdolSinger:]]

!!21 Ways

* ClingyJealousGirl: She comes off as being in a competition between her and Miki
* IdolSinger: Fairly well known one.
* {{Yandere}}: She will beat you up if you piss her off too many times.

!!Maeda Eriko

* SternTeacher: Alternately, she's a SadistTeacher depending upon interpretation.

!!Junko Watanabe

* PromotionToParent
* TomboyWithAGirlyStreak: She's a surprisingly good cook and is definitely the most motherly of the girls.