They're making a secondary offering - putting more shares on the market basically - of 3268200 (3+ million) shares at 5643 yen each, for a total of ~18 billion yen, which they claim is 5% below share price as of Jan 19. Anycolor's market cap is 168 billion yen so this is about 10% additional shares on the public market. Naturally that means that today the share price dropped 5% because that's how these things work, people otherwise would have an arbitrage opportunity so traders do that arbitrage pre-emptively. The price will likely be extremely stable at this level until the 24th when the additional shares are sold.
The shares will be offered on "international markets" but based on the language used it seems they're basically getting a financial institution (the underwriter) to sell the shares to so-called institutional investors, so no retail investor will immediately get their hands on these shares.
The 3 groups that are quoted are the ones selling the shares. You noted LC Fund which is a Chinese investor, I'll note Skyland Ventures which is owned by Riku who is cashing in to the tune of 451400000 yen, or ~3.5 million usd. Anycolor themselves won't make any money from this secondary offering. The remainder of the shares owned by the three groups are locked up and cannot be sold until April 23rd. Riku Tazumi also agreed to the same lock-up period.
I don't personally think this changes the decision-making of the company as Riku himself is still by far the largest shareholder, though he hasn't held an outright majority since after the IPO.
e: To put a point on the control thing, before the IPO Riku + Skyland (also Riku) had 51% of the shares. There was no way for anyone who held 15%, 10%, whatever, to have any real influence on the company if Riku didn't want them to. After the IPO those %s only dropped. For this reason I don't buy any narrative of Chinese investors having any significant control over Anycolor at any point.