{{MusicArticle
| titlejp     =こいしちゃんとおそとのせかい
| titlejprom  =Koishi-chan to O-soto no Sekai
| titleen     =Koishi-chan and the Outside World
| group       =[[Forest306]]
| groupCat    =Forest306
| image       =KCOS-0001.jpg
| banner      =KCOS-0001 banner.png
| catalogno   =KCOS-0001 
| tracks      =12
| length      =42:08
| genre       ={{Genre|Instrumental}}, {{Genre|Vocal}}, {{Genre|Folk}}, {{Genre|Rock}}
| released    =2012-08-11
| convention  =Comiket 82
| website     =[http://forest306.com/kcos/ Link]
| illustrator =
| designer    =
| arranger    ={{lang|ja|ポール}} ([[Sing, R. Sing!]])
: {{谷屋楽}} ([[Heta no Yokozuki]])
: mcn ([[J&B]])
: SS ([[マッカチン企画]])
: {{lang|ja|水月やまと}} (ICE MUSIC)
: {{lang|ja|みっつん}} ([[Applice]])
: {{lang|ja|だ}} ([[Forest306]])
| masterer    =
| lyricist    =
| vocalist    ={{谷屋楽}}
: {{lang|ja|うぇり}}
: {{パイン}} ([[マッカチン企画]])
: SS
: {{lang|ja|はるうら}} ([[榛ノ木書室]])
: {{lang|ja|紗々目ユキ}}
: Atori ([[As/Hi Soundworks]])
: Kuroa* (OruCoris{{lang|ja|の惑星}})
; Jacket Illustration
:{{lang|ja|桜居春斗}} ([http://mtrn.web.fc2.com/ METRONOME])
; Booklet Illustrations
:{{lang|ja|絆キセキ}}
:Fifiruu ([http://www.pixiv.net/member.php?id=615385 pixiv])
:{{lang|ja|ぱおの}} ([http://blog.livedoor.jp/paono_hi/ {{lang|ja|ぱおのーと}}])
:{{lang|ja|イチ}} ({{lang|ja|空中ブランコ}})
:{{ランコの姉}} ([[豚乙女|BUTAOTOME]]))
:{{lang|ja|如論}} ([http://moftea.blog36.fc2.com/ {{lang|ja|フデガタナ}}])
:{{lang|ja|ゾウノセ}} ([http://zounose.jugem.jp/ {{lang|ja|薬味さらい}}])
:{{lang|ja|紗々目ユキ}} (Corniche Arts)
:{{lang|ja|ぶーわ}} ([http://www.geocities.jp/je104049/ {{lang|ja|赤面と三角関係と私}}])
:{{lang|ja|ぱふキン}} ([http://www.pixiv.net/member.php?id=713683 pixiv])
:{{lang|ja|ながみん}} ([http://kiwibox.web.wox.cc/ Kiwi Box])
:{{lang|ja|すき}} ([http://crie-hp.at.webry.info/ CRIE])
:{{lang|ja|めえこ}} ({{lang|ja| アルパカ牧場}})
:{{lang|ja|優真}} ({{lang|ja|天球儀}})
:{{lang|ja|紗々目ユキ}} (Corniche Arts)
; Mastering
:Matthew Coxwall (Coxwall Studio)
| composer    =
| producer    =
| other_staff =

| description =It features vocal and instrumental arrangements of themes from ''[[Lotus Land Story]]'', ''[[Embodiment of Scarlet Devil]]'', ''[[Perfect Cherry Blossom]]'', ''[[Immaterial and Missing Power]]'', ''[[Imperishable Night]]'', ''[[Phantasmagoria of Flower View]]'', ''[[Mountain of Faith]]'', ''[[Subterranean Animism]]'', ''[[Undefined Fantastic Object]]'' and ''[[Ten Desires]]''.

It was released alongside a comic anthology.
| tracklist   =

* {{Track|01|{{lang|ja|きさらにとりぎ}}|03:38}}
** ''[[Wikipedia:Kisaragi|Kisaranitorigi]]''
** arrangement: {{lang|ja|ポール}} ([[Sing, R. Sing!]])
** original title: {{lang|ja|芥川龍之介の河童　～}} Candid Friend
** source: {{MoF}}

* {{Track|02|{{lang|ja|さよならお雛様}}|03:49|lyrics=Lyrics: さよならお雛様}}
** ''Farewell, Lady [[Hina Kagiyama|Hina]]''
** arrangement: {{谷屋楽}} ([[へたのよこずき|Heta no Yokozuki]])
** vocals: {{谷屋楽}}
** original title: {{lang|ja|厄神様の通り道　～}} Dark Road
** source: {{MoF}}
** original title: {{lang|ja|ハルトマンの妖怪少女}}
** source: {{SA}}

* {{Track|03|{{lang|ja|ももいろのゆきのなかで}}|03:02|lyrics=Lyrics: ももいろのゆきのなかで}}
** ''Within Pink Snow''
** arrangement: mcn ([[J&B]])
** vocals: {{lang|ja|うぇり}}
** original title: {{lang|ja|おてんば恋娘}}
** source: {{EoSD}}

* {{Track|04|{{lang|ja|ワンダーランド}}|03:45|lyrics=Lyrics: ワンダーランド (Forest306)}}
** ''Wonderland''
** arrangement: SS ([[マッカチン企画]])
** vocals: SS, {{パイン}} ([[マッカチン企画]])
** original title: {{lang|ja|月時計　～ ルナ・ダイアル}} 
** source: {{EoSD}}

* {{Track|05|{{lang|ja|六月、紫陽花、肝試し}}|03:19}}
** ''June, Hydrangea, a Dare''
** arrangement: {{lang|ja|水月やまと}} (ICE MUSIC)
** original title: {{lang|ja|死体旅行　～}} Be of good cheer!
** source: {{SA}}
** original title: {{lang|ja|リジッドパラダイス}}
** source: {{TD}}

* {{Track|06|{{lang|ja|七月、七夕、天の川}}|03:52}}
** ''July, Tanabata, Milky Way''
** arrangement: {{lang|ja|水月やまと}} (ICE MUSIC)
** original title: Twinkle, twinkle, little star
** source: Mozart
** original title: {{lang|ja|人形裁判　～ 人の形弄びし少女}}
** source: {{PCB}}

* {{Track|07|{{lang|ja|夏色ハート}}|03:30|lyrics=Lyrics: 夏色ハート}}
** ''Summer-colored Heart''
** arrangement: {{lang|ja|みっつん}} ([[Applice]])
** vocals: {{lang|ja|はるうら}} ([[榛ノ木書室]])
** original title: {{lang|ja|幻視の夜　～}} Ghostly Eyes
** original title: {{lang|ja|蠢々秋月　～}} Mooned Insect
** source: {{IN}}

* {{Track|08|{{lang|ja|ポピー}}|02:53|lyrics=Lyrics: ポピー}}
** ''Poppy''
** arrangement: SS ([[マッカチン企画]])
** vocals: {{パイン}} ([[マッカチン企画]])
** original title: {{lang|ja|眠れる恐怖 ～}} Sleeping Terror
** source: {{LLS}}

* {{Track|09|{{lang|ja|二秒半}}|03:44|lyrics=Lyrics: 二秒半}}
** ''Two and a Half Seconds''
** arrangement: {{谷屋楽}} ([[へたのよこずき|Heta no Yokozuki]])
** vocals: {{lang|ja|紗々目ユキ}}
** chorus: {{谷屋楽}}
** original title: {{lang|ja|ラストリモート}}
** source: {{SA}}
** original title: {{lang|ja|小さな小さな賢将}}
** source: {{UFO}}

* {{Track|10|November leaves|03:17}}
** arrangement: {{lang|ja|だ}} ([[Forest306]])
** original title: {{lang|ja|ポイズンボディ　～}} Forsaken Doll
** original title: {{lang|ja|今昔幻想郷　～}} Flower Land
** source: {{PoFV}}

* {{Track|11|{{lang|ja|聖夜と魔法使い}}|04:12|lyrics=Lyrics: 聖夜と魔法使い}}
** ''The Holy Night and the Magician''
** arrangement: {{lang|ja|だ}} ([[Forest306]])
** vocals: Atori ([[As/Hi Soundworks]])
** original title: {{lang|ja|恋色マスタースパーク}}
** source: {{IN}}

* {{Track|12|{{lang|ja|正月あるこあな}}|03:03|lyrics=Lyrics: 正月あるこあな}}
** ''Is therr a New Yearr?''
** arrangement: {{lang|ja|ポール}} ([[Sing, R. Sing!]])
** vocals: Kuroa* (OruCoris{{lang|ja|の惑星}})
** original title: {{lang|ja|萃夢想}}
** source: {{IaMP}}

}}