If there's an EULA that comes with the pack when you buy it, and it mentions the Violent Content Forbidden restriction, then please copy that EULA paragraph here and maybe I can make a better interpretation.
However, my first instinct is that you're good.
I would tend to think that "Violent Content Forbidden" refers to particularly brutal violence. Heavy blood and gore, onscreen killing that involves torture, or similar. Normal RPG violence is alright, even somewhat dark violence. Domestic violence would probably be OK to depict, as long as you don't depict it in a particularly graphic way, sexualize it (for the audience) in any way, or outright condone the domestic violence through your narrative tone.
I have looked through this like 500 times now I don't see it I paid for the steam version that mention no such restrictions
IMPORTANT, READ CAREFULLY.
PLEASE READ THIS END USER LICENSE AGREEMENT (THE "AGREEMENT") CAREFULLY BEFORE USING THIS RESOURCE PACK. IF YOU (THE "USER") DO NOT AGREE TO THE TERMS, CONDITIONS AND LIMITATIONS OF THIS AGREEMENT, PROMPTLY DELETE THE DIGITAL CONTENT FROM YOUR COMPUTER.
1. Copyright, trademark and other intellectual property rights of Add-on Series (the "Product") are property of KADOKAWA (the "Creator") and third party allowed by the Creator. The product is published by Degica Co., LTD (the "Publisher").
2. The resources included in the Product (the "Resource Pack") may be used with RPG Maker MV. Alternatively, you may use the Product with any other entry in the RPG Maker series that retains the Company's rights. User can create, distribute, or sell their original game by using the Resource Pack only if they meet all the following conditions:
2.1 You must be a legitimate user of our products. Your product must be registered to you. Registration is automatic at pack purchase via the official store or one of our recognized distributors. In some cases, you may be asked to provide a proof of purchase – such as order number, e-mail, address or receipt. Please keep this information handy.
2.2 You shall use the Product for game-creation and project-specific advertising media only (screenshots, videos).
2.3 Your game must include additional documentation that clearly indicates the use of the Resource Pack and the following copy:
[Copyright](C) KADOKAWA CORPORATION./YOJI OJIMA
2.4 Solely used for the creation of your game, you can edit, process, and modify the materials contained in the Resource Pack. You will not share these edits with others.
2.5 Do not sell, distribute, lease, or transfer the Resource Pack itself (even if the materials were edited, processed, or modified by the User), as a whole or any of its parts.
3. The Publisher will bear no responsibility for any damages to the User's computer caused by misuse of the Product.
4. By using the Product, the User accepts the full terms and takes sole responsibility for use of the Product.
5. The Publisher will bear no responsibility for any issues and disputes between third parties, regardless of the content, that occur as a result of the creation, distribution, and release of the User's game by using the Product.
------------------------------------------------------------ Pack Creator: KADOKAWA
Publisher Degica Co., LTD