普段はとてもおとなしいナイスガイだが、理性のタガがはずれると人格が豹変する二重人格。

Sentence Analyzer

普段はとてもおとなしいナイスガイだが、理性のたががはずれると人格が豹変する二重人格。

English Translation

He's got a dual personality—usually a quiet "nice guy" type, but when he flips, his character changes.

Furigana

普段(ふだん)はとてもおとなしいナイスガイだが、理性(りせい)のタガがはずれると人格(じんかく)が豹変(ひょうへん)する二(に)重(じゅう)人格(じんかく)。

Romanji

Fudan wa totemo otonashii naisugai da ga, risei no taga ga hazureru to jinkaku ga hyōhensuru ni jū jinkaku.

Words

普段 (ふだん)

usual; habitual; ordinary; everyday; always

は (は)

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

迚も (とても、とっても)

very; awfully; exceedingly; (not) at all; by no means; simply (cannot)

大人しい (おとなしい)

obedient; docile; quiet

ナイスガイ (ナイスガイ、ナイス・ガイ)

nice guy

だ (だ)

be; is; indicates past or completed action; indicates light imperative

が (が)

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

理性 (りせい)

reason; reasoning power; (one's) sense

の (の)

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

箍 (たが)

hoop; binding (e.g. of a barrel)

外れる (はずれる)

to be disconnected; to get out of place; to be off; to be out (e.g. of gear)

と (と)

if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)

人格 (じんかく)

personality; character; individuality

豹変 (ひょうへん)

sudden change; complete change

二 (に、ふた、ふ、ふう)

two