Lovely chapter! It's so cute how much more sweet and honest Itsumi is towards Rin now. Which enables Rin to be more assertive than ever. They have a great chemistry going for them.
It's funny that every time Itsumi got laid or almost laid (Makoto, Yayoi almost, and now Rin), it was without the love potion, and Itsumi acted very submissive. The other girls (the ones who still want her anyway) just don't know that all it takes to get with Itsumi is to be just a little dominant. She may not be able to tell love from lust yet, but she has accepted that she longs for intimate attention from girls (beyond just being popular and powerful). To the point where her initial dubious claims that she is not into Yuri have gradually turned into replies ranging from a "wow queen you are so beautiful", to a blushing "you perv", to a meek "yes queen".
On that note, I think it's cool that two of the three girls Itsumi got (mutually) intimate with never took the love potion. And in general, most of the girls are not really obsessed with her, and have a potential alternative love interest set up. Despite this being a harem, things have become pretty complicated, so I felt like making a relationship chart (which is very unlike me... this manga is messing with my brain).
Loves Itsumi, assertive, willing to go steady: Rin (no potion, slept with)
Likes Itsumi, assertive, not willing to go steady: Yayoi (no potion, fooled around with), Makoto (potion wore off, slept with, interested in Sachie)
Likes Itsumi, dependent: Himari (potion wore off), Kurohime (potion may still be in effect, might just need friends), Ruruka (no potion, only after her body)
Possibly likes Itsumi, not dependent: Tsubasa (potion wore off, likes R too), Yuina (no potion, loves Himari), Hana (no potion, Yuri enjoyer), Yomiko (no potion)
Neutral or unclear: R (potion wore off, loyal to Sachie), Hachou (interested in Himari), the ghost girls (potion, Itsumi can't see them), Unnamed delinquent (Yayoi's "stalker"), Minko (Makoto's maid)
Hostile: Sachie (no potion, loves/hates Makoto), Kakuko (Makoto's maid)
(This is of course just the state of affairs at chapter 25, so definitely subject to change.)