The rumour is that Shuichiro is set to sign professional papers with Misako gym, where he has been training recently, and will be making a professional debut either late this or very early next year.
As an amateur Shuichiro ran up an excellent record of 104-20 (55) whilst competing both nationally and internationally. His achievements include a major win in a national tournament as well as two runner up places in national competitions.
Having fought at 69KG's in the amateur ranks we'd be expecting Shuichiro, if and when he debuts as a professional, to be fighting at either Welterweight or Light Middleweight. Given those divisions are domestically quite weak there is not reason why he wouldn't be fast tracked through the ranks towards a title fight in single figure fights.
Whilst the rumour of his turn to the pros is still merely a rumour, it does seem like it's one with a lot steam and a really big chance at becoming a confirmed story in the coming days.