omg yesss i LOVE the random drops of unit fanbase characterizations !!! facts are sort of scattered throughout stories i don't know all ofc... here's at least a start of what i know!

fine

• i actually do not know too much about fine, but i do know they struggled a little in figuring out their formula; since while they had fans that enjoyed their aesthetic and music, they weren't able to reach the point where they would inspire others, particularly in becoming idols like them

Trickstar

• a lot of casual fans, especially because they sell themselves as a friendly unit that fans can relate and feel equal to
• subaru however particularly has more fanatical fans than the rest of the members, since the events of !-era SS caused a lot of people to feel a sense of protectiveness over him

RYUSEITAI

• lots of kids! their roots began with doing free hero shows for the children at the park nearby yumenosaki academy
• they particularly hope their performances bring hope to their young fans and make them believe in peoples inherent good
• they have a consistent and loyal fanbase
• shoutout to chiaki's increasing fanbase of female idols who like his face mentioned randomly in some stories

ALKALOID

• i actually don't know much about alkaloid's fanbase... i just know that they appear to have a fondness for their characters quite a bit!

Eden

• cospro's blueprint typically includes involving their idols in non-idol activities and a variety of non-live-activities, which allowed them to have powerful name recognition and build up a massive fanbase
• shoutout to eve's fujoshi fanbase (as they would appeal by teasing 'close but not too close skinship & gestures' (see: trap for you) lol)

Valkyrie

• their older fans are dedicated and hardcore, these fans would typically appreciate valkyrie from a distance with a semblance of respect (i always liked the detail that they would not even cheer following valkyrie's performance, as a way to give their art the highest respect)
• when valkyrie changed their performances to be less niche & begun to participate in public activities, they gained a wave of newer fans that tended to be more casual and run younger. because of this they have a somewhat noticeable "rift" between their fans
• despite their performances having a sense of maturity that utilize high art, there's a lot of young children who like valkyrie because it makes them feel mature. especially recently valkyrie's fanbase has gained a lot of children, especially since valkyrie has collaborated with brands that cater towards kids (like toys)

2wink

• they have a lot of children fans, as their acrobatic skills and tricks are very appealing for kids!
• when they were smaller, they found a lot of their success around the town's downtown area! they became well-known by those who live there and were typically appreciated by those who lived there, and as such could often get random non-idol jobs like just helping advertise for businesses and such
• prior to their image revamp, they sold themselves as a fully-synced twin unit who were very close. this resulted in a lot of fans who saw them as just a "pair of twins", without any actual ability to tell them apart or know their different individualities
• following their image revamp, they're working on fixing this and making sure they stand strong as individuals and are recognizable as individuals

Crazy:B

• definitely a fanbase that enjoys their antics and chaos! they enjoy their disobedience!
• crazy:b is a unit with a lot of controversy surrounding them, so those in the fanbase obviously do not care much about that
• iirc they're very reliable and loyal as they would consistently help crazy:b hijack lives in a way with their presence

...and i reached character limit halfway through lmao. check out the rest in my twitter crosspost!