An Inquiry Into Irreversible Phenomena, With Specific Regard to Changes of State

Joutai Henka Jikken ni Okeru Fukagyakuteki Jishou no Kousaku ni tsuite ((状態変化実験における不可逆的事象の考察について) is  Motojirō Kajii's character song, sung by Motojirō's seiyuu, Wataru Hatano. The song is included in  BUNGO STRAY DOGS Character Song Mini Album Vol.3 (『文豪ストレイドッグス』キャラクターソングミニアルバム 其ノ壱).

Lyrics
Romaji= Jinrui ga idaku eien no meidai wo tsuikyuu suru tame no purosesu Kibo wa katei doori hazeru yuukibutsu Joutaihenka wa areguro da!

Kiwamete…fukagyakuteki de Kiwamete…arifureteiru Keredomo…gimon no tsukinai――shi to iu jishou

Saiboutachi no himei sa Fukugou ongaku narihibiku Rabo wo mitasu remoneedo Donna aji ka oshietekure Bang!

Kokyuu kinou soushitsu noukan kinou haizetsu junkanki kinou no teishi Doukousandai hiseigyo nekurooshisu yosoku doori no deeta

Kanaderu issei ichidai no ritsudou Shiki suru no ga Tsumari wa…kono omosa nandana――wakitatsu yuetsu Nanto subarashii!

Kagakuteki ni tokenai Yue ni, sosoru tankyuushin Kanjou wo mitasu ekusutashii Motto motto oshietekure Oh!

“Saa, tanoshii tanoshii jiken no hajimari da!”

Kiwamete…gekiteki ni shite Kiwamete…makafushigi de Kyoumi wo…hikitsuke yamanai――shi to iu jishou

Saiboutachi no himei sa Fukugou ongaku narihibiku Rabo wo mitasu remoneedo Donna aji ka oshietekure Bang!

Kanji= 人類が抱く永遠の命題を　追求する為の過程(プロセス) 規模は仮定通り　爆ぜる有機物 状態変化は快活調(アレグロ)だ！

極めて…不可逆的で 極めて…ありふれている けれども…疑問の尽きない――――死という事象

細胞たちの悲鳴さ 複合音楽　鳴り響く 街 −実験室(ラボ)− を満たす檸檬爆弾(レモネード) どんな味か教えてくれ Bang！

呼吸機能喪失　脳幹機能廃絶　循環器機能の停止 瞳孔散大　非制御ネクローシス　予測通りの検証結果(データ) Find more lyrics at ※ Mojim.com

奏でる一世一代の律動 指揮するのが つまりは…この重さなんだな―――沸き立つ愉悦 なんと素晴しい！

科学的に説けない 故に、唆す　探究心 感情を満たす恍惚状態(エクスタシー) もっともっと教えてくれ Oh！

極めて…劇的にして 極めて…摩訶不思議で 興味を…惹き付けやまない――――死という事象

細胞たちの悲鳴さ 複合音楽　鳴り響く 街 −実験室(ラボ)− を満たす檸檬爆弾(レモネード) どんな味か教えてくれ Bang！

English= A process in pursuit of the eternal thesis that envelops mankind I’ve shrunken it to a testable scale, and, everything according to hypothesis, this bursting organic matter Changes states in a lively allegro!

Thoroughly…Such an irreversible, Thoroughly…Common thing, However…Is still an everlasting question: the phenomenon known as “death”!

The screams of cells combine into A complex melody ringing through the air Filling the streets—my laboratory—with my refreshing lemon bombs What does it taste like? Tell me, won’t you? Bang!

Respiratory function: lost. Brain stem activity: terminated. Circulatory system: ceased. Pupils: dilated. Uncontrollable necrosis. All data exactly as predicted!

Playing a once-in-a-lifetime rhythm And it’s all being directed by me In short…this weight is, most assuredly——the cause of my uncontainable joy How sublime!

Some things cannot be explained scientifically Therefore, in the spirit of inquiry, I must investigate Filling my emotions with unbridled ecstasy Tell me more and more, won’t you? Oh!

“Come now, it’s time for another superbly fun experiment!”

Thoroughly…In a dramatic way, Thoroughly…With an appropriate air of mystery, My interest…once piqued, cannot be contained: the phenomenon known as “death”!

The screams of cells combine into A complex melody ringing through the air Filling the streets—my laboratory—with my refreshing lemon bombs What does it taste like? Tell me, won’t you? Bang!