I'll bid you to look at other games by Alicesoft, namely:
Rance
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,
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,
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or
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,
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,
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,
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,
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,
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,
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, and
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(Note: Kichikuou is the closest to Sengoku in terms of gameplay so you might want to check that first)
(Note 2: 03, IX, and X have no available english translation as of currently, but the official english releases of the latter two are on the works by MangaGamer)
(Note 3: in case you weren't aware, Sengoku is the seventh game in the series)
Evenicle
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and
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Beat
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,
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, and
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(Note 4: again, no english translation for Ixseal)
Dai
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,
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, and
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(Note 5: no english translation for Daiakuji and Daitekoku, but this series has the most similar gameplay to Sengoku Rance)
and the other one-off entries like
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,
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, and the rest of the untranslated games
If that is not enough, you can also have a look at Leaf games, such as the
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series and the
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series, but they're not exactly eroges past the first entries and are pretty vanilla.
Off the top of my head, there's also the
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series,
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games (which are unfortunately untranslated aside from Kamidori, Rhapsody, and a number of only-interface patches for some others), and as a previous poster said, the Venusblood series of always-corruption-by-tentacles and at-least-one-loli-per-entry.