 If you liked
Yosuga no Sora
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 ...then you might like
Isekai One Turn Kill Neesan: Ane Douhan no Isekai Seikatsu Hajimemashita
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The idea of calling incest can be similar in these animes. Love between brother and sister which is considered to be taboo is shown in these two animes.
The characters want to take their siblings relationship to much further like a married couple. Though "One-Hit Kill Neesan" is not as sexual as "Yosuga no Sora" their main theme happens to be similar.
I warn you One-Hit kill Neesan can become boring compared to Yosuga no Sora but, as it is an isekai-adventure slow anime, give that a little time it won't disappoint you. Also both of them can be considered harem.