Shame it's oral-only but oh well. By the way, this is not the same girl as the Mujin story "Imouto Lips" (that's Miku, this is Mayu), and it seems the author is planning more oral-based stories in the Imouto Lip series.
psicomenace: indeed, like sister control or the ane koi book. The next Tenma-based book should be nice as well with a bit of yuri threesome, some chubby sister incest and so on.
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