Great guess,
you are actually right about the first part. She will complicate things for Sumire a bit, but after she tells her the truth, Shibata will become the second ally in her revenge. I'd say her part is almost as important as Mirai, she is a huge upgrade to Sumire's "team"
guess that's something to look forward to
i saw the cast list on MDL (jdrama/actor wiki), i think she looks pretty but other than some exaggerated or just having them be plain faced/no makeup and a 'frumpy' outfit + glasses, even the 'plain' type actors aren't bad looking
https://www.animenewsnetwork.com/encyclopedia/people.php?id=131715 like dang. apparently she's in the live action for prison school too and her imbd thumbnail is her with a bunch of guys like a harem or so, but i guess other than kids shows like sentai/power rangers it's hard to see any female actors that isn't in a rom com even if they aren't the lead but i think she's been in a handful of romances too (tho i guess other than an aged chara it's hard to pick an actor that looks 'bad/ugly' since it's expected to look good, typecasting aside versus some plain amateur and train them or so)
I’m actually shocked he said what he said on page 19 and didn’t catch himself.
i mean if he wasn't a hypocrite there wouldn't be a story, idk if shibata joined after his divorce/saw what sumire looked like before surgery tho but i mean he wouldn't exactly come off as good like "Yeah, you should put effort into your looks" lol (but i'm surprised the male coworkers didn't call them out on his words haha)