Frankly I didn't pay much attention to those sexual  scenes as someone did, because I knew it's not a conservative book, especially for a book written in the 1960s,  and also ,in Chinese version, which is more relevant to Original language, the words he used to referring sex seems nothing unusual than you have to breathe or eat to survive.

no doubt it's serious literature,because you can see ,those characters he created are so unique, yet have so much common personalities in human nature when you think deeply ,the beauty and the pain of falling in love as well, apparently ,Naoko and Watanabe  both have some sort of depression, after kizuki ‘s shocking suicide , Naoko’s situation is even more much worse , for those mentally troubled people ,as Reiko said, the problem is about trust, which is even more critical for lovers, both of them find it difficult to open their heart to someone ,Naoko fallen in love when watanabe wasn't really ready or before he understood his own feelings ,he mentioned he would leave between conversations and even asked about why she didn't have sex  with kizuki before at that special night,

So Naoko knew he didn't love her with all of his heart ,which is devastating for a depressed and mentally fragile 20 -year -old girl.

I think that's why she became more ill and got into this far away therapy care place 

But this is also the turning point, since then, Watanabe found it unbearable living in Tokyo without Naoko, he went to travel without any destination, he missed her a lot and always waited desperately for Naoko’s letters, when letters did came he read it again and again, felt like she's still with him and turning the hopeless situation into pleasant mood instantly.

The time when he visited Naoko in that therapy care center,I think he is so much in love and  happy ,that's why he recall those precious memories again and again to pull himself together and deal with all those bazaar after back to Tokyo alone.

After that you think they will happy ever after, came the saddest part, even deepest love can't last forever as promised, like the writer said at the first place, you thought you’ll never ever forget someone  ,she or he was so important and special , so perfect and is everything you could ever dreamed for, you couldn't live without her, how could you possibly forget her? But actually you will, eventually, everything will fade away with time.

How sad.

So after he waited and waited for Naoko’s return, even prepared all the  furnitures and decorations in the new home, he didn't know that, for those people with depression ,you have to be very very patient ,Naoko felt the pressure of having to recover quickly and be back, that pressure made her collapsed again.

For desperate Watanabe, he couldn't miserably waiting any longer, then Midori came into his heart just about  time, she was only lucky enough to be there in the right moment, just like Watanabe said he wouldn't have kissed Midori at that afternoon if not because of the sudden fire, she is so different from Naoko, so alive and joyful even though she actually lived such painful and sad life.grown up as the  only poor among very rich privileged kids , always has to beg her mom even for just several bucks, looking after sick mom for years before lost her , now dying dad again , in a word,  this poor young girl is just extremely exhausted for years.yet  still she managed to handle all the hardship without becoming a miserable complainer ,but joyful, incredible ,interesting ,creative  lovely women ,strong both physically and spiritually. And more like a summer breeze or bright light compared with other lost generation around them, No wonder Watanabe fell for her, and said only Midori made the outside world not so horrible to live in.

I think for those sexual fantasies, it's only Midori’s way to ease the pressure of life, like she and her sweet sister did cursing others instead of crying to relieve the pain of his father’s death, But those fantasies did make her quite the opposite way from Naoko, whose depression and the grief of losing best friend Kizuki suppressed all other emotions , including long term lack of desire for sex.

Meanwhile I think  Nagasawa is also right about Watanabi ,that he is selfish and cares about himself more than others,  that's why he wrote to Reiko about his new love ,didn't consider the shock and disappointment he would bring to poor Naoko, when love fade into just responsibilities, he only thinks he has to be honest with himself.and only realized how cruel he was and how he mistreated his hometown girlfriend after Naoko's suicide, He regretted painfully , his suffering is such an utterly unbearable torture  that he couldn't sleep or find peace in his heart, what he could only do is wandering around without purpose, made himself drunk enough or tired enough to sleep, careless about what to eat or where to sleep, the traveling is more like self-exile or self-punishment.

All though, I really hate the fact that he eventually get back to Midori just one month later,

But that's life, dead remains dead for ever,  the living  lovers still have to live on, its only a matter of time for watanabe to go back to his new love, years later ,eventually forget about Naoko.

All those memories ,no matter sweet or bitter ones ,are left somewhere in time.