Not sure whether this is an elaborate stealth marketing attempt to make people give Kiniro Mosaic a try (if so, well played) but the opening sequence in question didn't seem bad to me at all. I think they were just mixing up the angles to prevent it being visually boring, and there wasn't a trace of inappropriate sexualisation (the kind of person who considers bare legs on innocent schoolgirls to be seedy would probably also find a lot of other innocuous stuff questionable). I'd show it to my kid brother without a second thought. Though he'd be disappointed by the lack of explosions and lava.
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