I guess the seniority in H!P is the most important part (the reason why Captain is the leader of H!P right now and not Sayu or why Kaorin was leader instead of Kemeko).

But as you say, Haruka is so much younger than the other girls, so I guess they will give her someone to support her. But as long as she’s just subleader it might be okay even at her age. I’m sure Mizuki will stay long enough.

Well, I get why Captain is leader of H!P. She was part of Kids, which is before Michishige’s time. I get that… But say if… random, but Airi were to join Morning Musume (FOR NO GOOD REASON), would she be leader? Or would it go to the seniors of MM (Mizuki)? Doesn’t seniority in H!P only count for becoming leader of H!P, not the group?

Or another example (that’s also pulled out of my ass): Say Momoko had joined H!P, like, 5 days before Captain did (SHIT DON’T MAKE SENSE), would Momoko be the leader of BK? Would Momoko be becoming the leader of H!P right now? 

UUUUUUHHHHH

I think Momoko would. Mikitty became the leader of MM after Yossy’s graduation not because she was older than 5th gen but because she has been a member of H!P since the 4th gen auditions.

I just can’t picture, as young as Haruka is, her becoming leader of MM. At all. I mean, maybe if her gen. were the senior-most members. But there’s an entire gen. of decently older girls ahead of her in Morning Musume and I picture one of them becoming leader before she should. I mean, say if Mizuki (she’s, what, about 3 or so years older?) were to leave MM after 6th gen., with no new additions to MM, would Haruka be the leader? She’s literally the youngest. I mean, by my logic, Haruna would be the new leader. But I completely understand why, despite being older than the other new girls, she wouldn’t be the leader. But I kind of see Haruka as being the baby of MM and it’d be so ‘off’ for her to take the leader position. It’d be backwards, really, despite there being some decent reasoning behind it.

Answering these in (sort-of) order:

The Mikitty case proves that MM leadership goes by overall H!P seniority. So yes, Haruka is next in succession after Mizuki, weird as it may seem.

Fun fact about Kaorin’s leadership: going strictly by the Seniority-Then-Age rule, Nacchi SHOULD have been leader of MM (she’s older by 3 days) but she actually ceded leadership to Kaorin.

If Airi randomly joined MM, she would indeed become leader because she pre-dates all the others. (Again, refer to the Mikitty case. H!P seniority trumps everything else even within MM.)

If Momoko had secretly/randomly gotten into H!P before Shimizu & the rest of the kids, she would be the real Captain of BK AND soon-to-be Supreme Leader of H!P.

So yes, the seniority rule means Haruka will be sub-leader when Mizuki takes over, regardless of age. She may be the “baby,” but she already bosses around all the 9ths and 10ths anyway. She’s level-headed, has the experience, and acts older than she is, so she’s probably better-suited for a leadership role than most realize.

More fun facts: IN REAL LIFE, Momoko is two graduations away from becoming Supreme Leader of H!P – if Captain and Maimi decide to leave, she’s next in line (age rule).

More fun facts over: If the Pandas were still around after Risa/Aika’s grad, the next in line after Sayu and Reina would be Linlin. She’s younger than Junjun but has seniority because she had been in H!P Eggs prior to joining MM.