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Shun MatsubaraMarketer × AI builderTokyo

I’ve moved real numbers in ads, social and SEO. Now I make and run the work with AI and systems I built myself.

See the work →Contact
Real AI-made work and view counts
¥30M

Monthly Meta/TikTok ad spend managed

ONE · 2025.10–2026.05
200→800%

ROAS on my accounts

RASA JAPAN · 2025
38K

Men’s beauty Instagram followers, from 1K in ~8 months

セスグモ · 2025
38,730

Views on one AI drama episode (2 days)

YouTube · 2026-11-14
Now

What I’m doing now

Running my own ventures and student orgs alongside contract marketing and AI work.

2026.08–

NexAI / Employee Store

Co-founder (CEO-designate)
Building and running a marketplace that lists AI agents as “AI employees” and connects them with buyers. The company is being incorporated.
2026.09–

STAMP / HOOK CLUB

Founder
Starting a student org for working with the world from Japan, and a student-only collective that runs social and short video for companies.
2026.10–

honkoma Inc.

Marketing contractor
Marketing strategy and KPIs for an AI service, a short-video generation pipeline, and social testing.
2026.09–

Arche Inc.

Social & web marketing contractor
For care and welfare providers: social scripts, LINE funnels, sales lists and weekly GA4 reporting.
2026.08–

YOUTRUST (MOMENTUM HUB), Dokuji Rosen Inc., AI Henshu Studio Inc.

Social operations & automation
Community events for the YOUTRUST career network, launching X and note for Dokuji Rosen, and fully automated X for AI Henshu Studio.
2026.10–

Official AI-tool ambassador

HeyGen (1st cohort), AIReel, TANKA, Manus
I only promote tools I actually use, with real examples.
Works

Selected work

From vertical AI dramas to a 10-minute explainer and ads. Hover a video to play it.

YouTube
YouTube
01 / 05Details →

Vertical AI drama: “Wrong Person to Mess With”

11 start frames lock cast, wardrobe and set so every cut keeps the same face.

Image genVideo genElevenLabsffmpeg
38,730views on Ep.1 in 2 days
Instagram
Instagram
Instagram
02 / 05Details →

Baby Interviewer (14-episode series)

Same face and suit every episode; off-model takes are remade, not posted.

Image genVeo 3.1Video gen
52,271views across 6 episodes (top: 20,916)
TikTok
03 / 05Details →

Founders in 90 seconds: FOUNDERS FILE

Short lines built on numbers and contrast; only the key words get big captions; money shown as newspaper-clipping cards.

ElevenLabsPythonffmpeg
13,100views on the Masayoshi Son episode in 1.5 days
YouTube · 10:34
04 / 05Details →

A 10-minute science explainer

Measured a reference channel into 15 rules; 6+ visual changes per minute in the first 5 minutes.

ElevenLabsRemotionffmpeg
10:34narration, 14 generated clips, 11 animated diagrams
Seedance 2.5
Agent × Canvas
Higgsfield
05 / 05Details →

Vertical ads made with Renoise

Chained cuts by passing each last frame forward; driven from Claude Code via CLI.

Seedance 2.5Seedance 2.0Agent × Canvas
Seedance 2.5Renoise vertical ads and a Higgsfield outfit transition
All work →
AI systems

The systems I run with AI

Not just building: I own the systems that keep it running every day. All figures are measured.

  1. 01

    Measure what works

    Collect what’s growing; count length, cuts and the first two seconds.

  2. 02

    Turn it into a format

    Turn the counts into rules; lock characters and look.

  3. 03

    Build with AI

    Images, video, voice and code, each with the best tool for the job.

  4. 04

    Fix with numbers

    Read the numbers after publishing, fix the next one, automate the loop.

361

Always-on automation jobs

Posting, metrics, replies and SEO run as launchd jobs: 240 on a MacBook, 121 on a Mac mini.

launchd · 2026-11-14
5,803

Commits in 6 months

May–Oct 2026 across 144 repos. Claude Code and Codex implement; I design and verify.

git · 2026.05–10
31

Social accounts on 2 phones

Genre channels posting daily from two Android phones via adb.

fleet · 2026-11-14
1,223

Wiki pages my agents read

Decisions, mistakes and playbooks, plus 437 custom skills, loaded into every task.

Obsidian · 2026-11-14
AIClaude CodeAICodex CLIAIGeminiAIElevenLabsAIHeyGenAIHiggsfieldAIRenoiseAIKlingVideoRemotionVideoFFmpegVideoBlenderVideoThree.jsVideoCapCutVideoHyperFramesAIClaude CodeAICodex CLIAIGeminiAIElevenLabsAIHeyGenAIHiggsfieldAIRenoiseAIKlingVideoRemotionVideoFFmpegVideoBlenderVideoThree.jsVideoCapCutVideoHyperFrames
DevTypeScriptDevNext.jsDevReactDevHonoDevCloudflare Workers / D1DevSupabaseDevStripeDevPythonOpslaunchdOpsAndroid + adbOpsGA4 / Search ConsoleOpsAhrefsOpsObsidianOpsFigmaDevTypeScriptDevNext.jsDevReactDevHonoDevCloudflare Workers / D1DevSupabaseDevStripeDevPythonOpslaunchdOpsAndroid + adbOpsGA4 / Search ConsoleOpsAhrefsOpsObsidianOpsFigma
Career

Career

Economics student at Hosei University. Since 2024 I’ve worked with 10 companies across HR, ads, social and e-commerce, owning both strategy and execution.

2025.10–2026.05

ONE Inc.

Head of Media & Ad Management
Led marketing for the NEWMATCH dating app in a CMO-like role, plus 12+ owned-media teams.
¥30M/mo ad spend~50-person org
2025.12–2026.05

ABABA Inc.

Owned-media SEO director
Built a three-pillar SEO plan (CVR, ranking rewrites, new articles) from GA4, GSC and Ahrefs.
27K+ sessions/mo on target pages
2025.08–2025.12

Athena Technologies

Recruiter
Sourcing via Wantedly, personalized outreach and student-org partnerships.
2025.05–2025.09

clout Inc.

Apparel ad strategy & inventory planning
Shifted ad budget by per-SKU sell-through.
Hero SKU +250% YoY
2025.04–2025.09

SIXTYPERCENT Inc.

PR & influencer marketing manager
Sourced, negotiated and contracted influencers for a cross-border mall (10 countries, 1,500+ brands).
2024.10–2025.07

RASA JAPAN Inc.

Performance-ads team lead
Google/Meta/TikTok bidding and creative A/B tests for travel and lodging.
ROAS 200%→800%
2024.10–2025.05

Sesugumo Inc.

Head of social marketing & branding
Ran the HOMCOS men’s-beauty Instagram; redefined the persona and positioning.
1K→38K followers
2024.09–2025.03

Mercari, Inc.

Customer success (Mercari Hallo)
Standardized onboarding for new business customers.
2024.08–2025.03

GMO NIKKO Inc.

Owned-media director
Ran a newly launched media with 2 interns and ~10 freelance writers.
2024.04–2024.07

SHiRO Inc.

Intern-team lead
KPIs and leader training for a ~200-person intern org, plus B2B sales.
Booking rate 20%→35%
Products

Things I’ve built

Services I took from idea to build, launch and growth.

Employee Store

Live

A marketplace to find and hire AI agents as “AI employees”, payment to delivery on one site.

employeestore.app↗

Day91

Live

A job board of paid long-term internships with a retention bonus on day 91.

day91.jp↗

crefi

Live

Matches creators who allow affiliate links with partners who promote them.

crefi.jp↗

STAMP

Recruiting

An inter-college student org for working with the world from Japan.

stamp-students.com↗

HOOK CLUB

Launching

A student-only social and short-video production collective.

hookclub.jp↗

Dot Dungeon

Live

A 2-minute pixel RPG with a new dungeon every midnight.

dot-dungeon.pages.dev↗
Accounts

Accounts

I’m @ummshun. I also run the AI account “Lily” (@bokuwalily). Followers as of 2026-11-14.

X638@ummshunMe. DMs openX9,693@bokuwalily (Lily)AI, automation and marketingnote3,705bokuwalilyMaking-ofs and guidesInstagram416@ummshunPersonalLinkedInummshunCareerGitHubummshunSmall tools for Claude Code and SEO

Official AI-tool ambassador: HeyGen (1st cohort) · AIReel · TANKA · Manus

Play

Which one got more views?

Two videos I actually posted. Which one got more views? Every number is real. See how long a streak you can build.

Streak 0Your best 0

Tap the one you think won

Contact

Let’s move the numbers, and build the system behind them.

I help with hands-on social, ads and SEO, and with AI production and automation. DM me on X or email.

DM on X →Email
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