The interview focused almost entirely on personality questions just to see whether you fit the company and asking whether you are ok with lots of business trips. The interviewers (Partner, Senior Manager, Manager) were all very friendly and happy to answer any questions. My interview was entirely in Japanese, but some staff don't speak a lick of Japanese so don't worry too much about that.

The interview in HLS took me more than one month. The interview process divided into three parts, manager, senior manager, and partner. The whole process took almost two hours. I used skype to interview and stayed online when the interviewer changed. Most questions are behavioral questions and easy to answer if you know your resume well, except for one technical question (not hard to answer too). Japanese is not required, but I think Japanese will be a plus at there definitely.