diff --git a/src/ja/momonga/build.gradle b/src/ja/momonga/build.gradle
new file mode 100644
index 000000000..da5ec80b4
--- /dev/null
+++ b/src/ja/momonga/build.gradle
@@ -0,0 +1,8 @@
+ext {
+    extName = 'MomonGA'
+    extClass = '.MomonGA'
+    extVersionCode = 1
+    isNsfw = true
+}
+
+apply from: "$rootDir/common.gradle"
diff --git a/src/ja/momonga/res/mipmap-hdpi/ic_launcher.png b/src/ja/momonga/res/mipmap-hdpi/ic_launcher.png
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diff --git a/src/ja/momonga/res/mipmap-xxxhdpi/ic_launcher.png b/src/ja/momonga/res/mipmap-xxxhdpi/ic_launcher.png
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diff --git a/src/ja/momonga/src/eu/kanade/tachiyomi/extension/ja/momonga/MomonGA.kt b/src/ja/momonga/src/eu/kanade/tachiyomi/extension/ja/momonga/MomonGA.kt
new file mode 100644
index 000000000..830e02b73
--- /dev/null
+++ b/src/ja/momonga/src/eu/kanade/tachiyomi/extension/ja/momonga/MomonGA.kt
@@ -0,0 +1,160 @@
+package eu.kanade.tachiyomi.extension.ja.momonga
+
+import eu.kanade.tachiyomi.network.GET
+import eu.kanade.tachiyomi.source.model.Filter
+import eu.kanade.tachiyomi.source.model.FilterList
+import eu.kanade.tachiyomi.source.model.MangasPage
+import eu.kanade.tachiyomi.source.model.Page
+import eu.kanade.tachiyomi.source.model.SChapter
+import eu.kanade.tachiyomi.source.model.SManga
+import eu.kanade.tachiyomi.source.model.SManga.Companion.COMPLETED
+import eu.kanade.tachiyomi.source.online.HttpSource
+import eu.kanade.tachiyomi.util.asJsoup
+import keiyoushi.utils.tryParse
+import okhttp3.HttpUrl.Companion.toHttpUrl
+import okhttp3.OkHttpClient
+import okhttp3.Request
+import okhttp3.Response
+import java.text.SimpleDateFormat
+import java.util.Locale
+
+class MomonGA : HttpSource() {
+    override val lang = "ja"
+    override val name = "momon:GA"
+    override val supportsLatest = false
+
+    override val baseUrl = "https://momon-ga.com"
+
+    override val client: OkHttpClient = network.cloudflareClient
+
+    // Chapters
+
+    private val dateFormat = SimpleDateFormat("yyyy年M月d日H時", Locale.ENGLISH)
+
+    override fun chapterListParse(response: Response): List<SChapter> {
+        val document = response.asJsoup()
+        return listOf(
+            SChapter.create().apply {
+                name = "単一章"
+                url = response.request.url.encodedPath
+                date_upload = dateFormat.tryParse(document.select("#post-time").text())
+            },
+        )
+    }
+
+    override fun imageUrlParse(response: Response): String = throw UnsupportedOperationException()
+
+    // LatestUpdate (Not supported)
+
+    override fun latestUpdatesParse(response: Response): MangasPage =
+        throw UnsupportedOperationException()
+
+    override fun latestUpdatesRequest(page: Int): Request = throw UnsupportedOperationException()
+
+    // Details
+
+    override fun mangaDetailsParse(response: Response): SManga {
+        val document = response.asJsoup()
+
+        return SManga.create().apply {
+            document.select("#post-tag > div.post-tag-table").forEach { div ->
+                when (div.selectFirst("div.post-tag-title")!!.text()) {
+                    "サークル" -> {
+                        artist = div.select("div.post-tags > a").joinToString { it.text() }
+                    }
+
+                    "作者" -> {
+                        author = div.select("div.post-tags > a").joinToString { it.text() }
+                    }
+
+                    "内容" -> {
+                        genre = div.select("div.post-tags > a").joinToString { it.text() }
+                    }
+
+                    else -> {}
+                }
+            }
+            title = document.selectFirst("#post-data > h1")!!.text()
+            thumbnail_url = document.selectFirst("#post-hentai > img")?.absUrl("src")
+            status = COMPLETED
+        }
+    }
+
+    // Pages
+
+    override fun pageListParse(response: Response): List<Page> = mutableListOf<Page>().apply {
+        val document = response.asJsoup()
+
+        document.select("#post-hentai > img").forEachIndexed { index, element ->
+            add(Page(index, imageUrl = element.attr("src")))
+        }
+    }
+
+    // Popular
+
+    override fun popularMangaParse(response: Response): MangasPage {
+        val document = response.asJsoup()
+
+        val lis = mutableListOf<SManga>()
+        document.select("div.post-list > a").forEach { element ->
+            lis.add(
+                SManga.create().apply {
+                    setUrlWithoutDomain(element.absUrl("href"))
+                    title = element.selectFirst("span")!!.text()
+                    thumbnail_url = element.selectFirst("div.post-list-image > img")?.absUrl("src")
+                },
+            )
+        }
+
+        return MangasPage(lis, document.selectFirst("div.wp-pagenavi > a.nextpostslink") != null)
+    }
+
+    override fun popularMangaRequest(page: Int): Request = GET("$baseUrl/popularity/", headers)
+
+    // Search
+
+    override fun searchMangaParse(response: Response): MangasPage = popularMangaParse(response)
+
+    override fun searchMangaRequest(page: Int, query: String, filters: FilterList): Request {
+        val urlBuilder = baseUrl.toHttpUrl().newBuilder().apply {
+            if (query != "" && !query.contains("-")) {
+                addQueryParameter("s", query)
+            } else {
+                val path =
+                    filters.filterIsInstance<UriPartFilter>().joinToString("") { it.toUriPart() }
+                addEncodedPathSegments(path)
+            }
+        }
+
+        if (page > 1) {
+            urlBuilder.addPathSegments("page/$page")
+        }
+
+        return GET(urlBuilder.build().toString(), headers)
+    }
+
+    // Filters
+
+    override fun getFilterList() = FilterList(
+        CategoryGroupFiler(),
+    )
+
+    private class CategoryGroupFiler : UriPartFilter(
+        "カテゴリーグループ",
+        arrayOf(
+            Pair("同人誌", "fanzine"),
+            Pair("商業誌", "magazine"),
+            Pair("急上昇", "trend"),
+            Pair("人気", "popularity"),
+            Pair("高評価", "rated"),
+        ),
+    )
+
+    private open class UriPartFilter(
+        displayName: String,
+        val vals: Array<Pair<String, String>>,
+        defaultValue: Int = 0,
+    ) : Filter.Select<String>(displayName, vals.map { it.first }.toTypedArray(), defaultValue) {
+        open fun toUriPart() = vals[state].second
+    }
+}