I wouldn’t put money on it being outright sinister or harmful, and it’s definitely fine to be into anime with characters like this. But I do find it odd to be into pictures like this enough that you add them to unrelated blog posts.
I remember a template for technical design documents that had a placeholder to insert a header image. Any image, could be totally unrelated to the document content. The template explains that it's a sort of mnemonic to identify the document, since everyone is expected to use the same template, and all walls of text roughly look similar to each other from a distance.
So with some header image, reader might be able to recall "it's that Clice post with Yami on top" or "it's that other Clice post with Kessoku Band".
Wait until you see magazine ads or such showing girls. The atrocity...!
It's literally just an arbitrary Attention-Grabbing Picture in the header; because there is really no good attention-grabbing header picture for a C++ language server. A (likely AI-generated nowadays) screenshot of VS Code just doesn't quite cut it — so non-corporate people just put some moderately interest-piquing picture, generally of things they themselves find "nice" to look at. Sometimes it's some silly meme/image macro, sometimes it's a random screenshot from an anime.
Like, here's a random example: [0]. An article is about "a Go-native shell sandbox with coreutils, Python via WebAssembly" — and it opens with a photo of "a sea lion sleeping peacefully on a rocky beach while other sea lions lounge in the background near the water". Why? Because the author thought it would be nice to put there, that's why! No deeper meaning, unless you want to do psychoanalysis over the Internet.
[0] https://xeiaso.net/blog/2026/dancing-mad-sandboxing/