I just started reading 彼女 お借りします in order to improve my reading fluency as well as getting some immersion. However, I have been struggeling reading parts which are not writting in standard printed Kanji and Kana. I suppose the sections I am talking about can be considered to be in a style more similar to handwriting. But I am not sure if thats actually correct since using circles instead of 口 seems really weird to me. For anyone who is in posession of the manga: an example can be found on page 30ish (32 in the digital version) of the first manga.
Any tips or recources which can help me getting better in reading non standard prints or handwriting?