The Real "Guilt" Isn't the Soda — It's Your Student Management Notebook
Suntory's new carbonated drink "NOPE (Guilty Soda)" is blowing up on social media. Apparently, its combination of sweetness and spice is "sinfully delicious."
But here's the thing, fellow tutors.
Isn't the real guilt the fact that it's 2026 and you're still tracking lesson records by hand?
I get it — you want to say, "But handwritten notes have a personal touch…" That's like saying "I bought a salad for my health" while dropping three bottles of Guilty Soda into your convenience store basket. It feels productive, but it doesn't actually solve anything.
・You manually count each student's lesson totals at the end of the month
・You spend 5+ minutes flipping through your own notes asking, "What did we cover last week?"
・You can't immediately answer when a parent asks, "How many lessons did we have this month?"
・You've manually entered data into Excel → made a copy-paste error → sent an incorrect invoice
How Much Time Is Manual Student Management Actually Costing You?
You might think, "It's not that big a deal." But when you add it all up, here's what it looks like.
With 10 hours, you could teach 2–3 additional students. In other words, sticking with manual work is the same as throwing away ¥20,000–30,000 every month. Now that's the real guilt.
What Does "Automating Student Management" Actually Mean?
"Automation sounds nice, but I can't code" — don't worry. With Kagemusha System, all you have to do is add events to your Google Calendar like you already do, and everything else is handled.
Step 1: Add Lessons to Google Calendar
Just create an event like "Taro – Math" the way you normally would. No special formatting required.
Step 2: Lesson Records Are Automatically Logged
Kagemusha System reads your calendar events and automatically records them in a spreadsheet, organized by student and subject.
Step 3: Generate Invoices with One Click at Month-End
It auto-calculates lesson count × rate and generates a PDF invoice, with the parent's name and address filled in automatically.
Manual Work vs. Kagemusha System: How Big Is the Difference?
| Category | Manual (Guilty) | Kagemusha System |
|---|---|---|
| Lesson records | Handwritten notes or manual Excel entry | Auto-synced from Google Calendar |
| Per-student tallies | An hour of calculations at month-end | Real-time automatic totals |
| Invoice creation | Manual copy into a template | Auto-generated PDF |
| Parent reports | Typed out manually via LINE | Auto-generated from lesson records |
| Data storage | Risk of total loss if your PC crashes | Safely stored in your Google account |
| Monthly cost | ¥0 (but a massive loss in hourly terms) | ¥500 (the price of 3 canned coffees) |
Frequently Asked Questions
Graduate from "Guilty"
Suntory's Guilty Soda is a drink that lets you enjoy a little indulgence. But there's nothing enjoyable about the guilt you feel from managing students by hand.
For ¥500 a month, you get 10 hours of free time back. Use that time to take on more students, invest in your own learning, or kick back with a Guilty Soda and watch Netflix.
Isn't it time to end the guilt of manual work — starting today?
Setup takes 5 minutes. If you have a Google account, you can get started right now.
👉 Visit the Kagemusha System official website
Still managing tutor attendance manually?
Discover Kagemusha System