--responding to @needs native check--
added punctuation.
believe it doesn't match the Japanese completely.

I believe the tag can be removed.

I think this sentence is fine (except that I think the comma should be inside the quotation marks).

@AlanF_US
Need confirmation :)
The comma inside or outside?

It should be inside, according to the AP Style Guide, the MLA Handbook, and various other sources.

Thanks.

@sundown, also in British English?

@morbrorper

Yes, the comma should be inside in British English, too, because what precedes it is a full sentence. By contrast, if it were just one word in quotation marks, then British English would put the punctuation outside. For example:

The boy said he was too old to be playing with "bugs".

I've noticed a fair bit of confusion in what some online sources say about British punctuation of quotations — even sources you'd expect to know better. Going into any bookshop, newsagent or library in Britain would help clear up the confusion.