快樂 vs 快楽

I was thinking of writing the difference between 快樂 (faailok) in Chinese and 快楽 (kairaku) in Japanese as 快樂 was the term you'd hear often when Mid-Autumn festival was approaching (people would say "中秋節快樂！" to each other), and those are used quite differently in Chinese and Japanese, though the characters are basically the same.

Then yesterday at the Cantonese lesson, there was the word 階段 which I learned means a level or stage in life in Chinese while it usually means just physical steps or stairs in Japanese.

Gaby raised another example of 大丈夫. In Japanese it means something like "no problem", but in Chinese it means a big man. Chinese is quite literal in this one.

She also asked me about what 馬鹿 (baka) meant in Japanese. She said she saw the word when she was playing a Gundam video game which came from Japan. This word doesn't exist in Chinese in the sense we Japanese use, which is "stupid." I thought there had been some history to it as to why those characters were used, but as I searched on the internet, it seems it's just another case of ateji.

Anyway, back to the topic of 快樂 and 快楽, the former is mostly used in expressing the joy of festivity in the Chinese culture, but in Japanese the original meaning has very much faded and it means indulging kind of physical pleasure (thus sexual pleasure most of the time), which is apparent when you do the image search by the word. Then I wonder what the equivalent of Japanese 快楽 is in Chinese.