Pros
Depending on your team, it can be hit or miss. When I joined Rakuten, I was lucky to have joined such a great team with nice Japanese manager and fun teammates. Stable. You will never get fired no matter how incompetent you are. Unless of course, you cheat or misbehave. Looks good on the outside. Rakuten is very famous in Japan, and you will almost 99.99% of the time get approved when you apply on anything (eg. rent, utilities, credit cards, etc). Can be a good launchpad to other companies. Looks good on your CV. Free quality meals 3x a day (pre-covid) Many benefits like free concerts, free game passes, discounted items, etc. Opportunity to work with a lot of people from different countries. Many internal trainings and online courses that you can enroll.
Cons
Depending on your team, it can be hit or miss. Some teams are excellent, some are the worst of worst. Avoid Rakuten Ichiba at all cost. Micromanagement and power harassment exists. There are some incompetent middle and "senior" managers who does nothing but approve attendance, holiday leaves, and production releases. Most of them have Dunning-Kruger syndrome. To cover up their incompetencies, they ask irrelevant questions during meetings to make themselves feel good. Always on call even after office hours. You are always required to bring your company phone to respond to incidents even though you are not an SRE person. :( Overnight work during monthly maintenance and load testing sessions. :( Blame culture. Engineers don't get any gratitude especially when resolving incidents. But instead, gets all the blame. T_T