There's 1 more chapter and IF which, from what I heard, is an alternate ending. I meant wrap up as in how they'll end the story, how this whole time leaping stuff works, and if Umeko really just a future time leaping Sakura, etc.
Trinitia scans, the previous (current?) group, has scans up to chapter 47 on their site. Not sure why they haven't uploaded it here, though. Pretty annoying having to juggle through a bunch of group sites just to remember what stuff is being updated.
In the context of things, Akira is just marking Kotaro as hers but our dense MC is focusing on the literal words (spit). https://jisho.org/search/%E5%94%BE%E3%82%92%E4%BB%98%E3%81%91%E3%82%8B and https://kano.ac/posts/2017-11-23_10-56.html for some information on its usage. I'm only a Genki Lvl...
Considering she mentions "dolls," I'll assume that her skill is more so controlling puppets/marionettes (or maybe even necromancy) and thus the whole "Life Bestowal" (生命付与) meaning. This is purely off the context clues. Maybe a raw reader can clear this up.
Jisho shows some other ways the name could be read but in this case it is Maimi (because furigana). I guess if you break it down, her name literally means "Dancing Sea" but that relies on an outdated usage of "舞".
MTL translations are alright if you can supplement it with knowledge of Japanese...
The sister's name should be "Maimi" if you read/translate the furigana. While "海" is read as "umi", in the usage of her name the "u" is dropped. I don't know why that's the case as I only know basic Japanese grammar.
Subtle stuff with Tsubasa writing "人" three times on the sand as a sign of nervousness. IIRC, there's a Japanese tradition (?) where they write "人" three times on their pal mand then "eat" it to get past nervousness.
Ishimaru said "ふ懐で プレイしないでください" (fu- futokoro de prei shinai de kudasai) which literally means "Please don't play near my chest/arm." https://jisho.org/search/%E6%87%90 for the context of "懐." The translation is fine since it's a more natural way of speaking.