Do you know what OVA means? This stands for Original Video Animation. This is a type of animation that is targeted towards a specific audience. This explains why this may be more explicit as compared to other forms of anime. The OVAs are usually shorter than the normal anime series. Take note that there are some differences that are available between the OVA and the usual anime series.
For example, the OVA can only be available through the DVDs that will be released. The OVA is also not exactly associated with the anime series.
To properly answer this question we first need to define what OVA means. OVA stands for Original Video Animation. The difference between OVA, regular episodes and specials is that OVAs are made to be released only on VHS, DVD or however you watch shows at home.
No OVAs are meant to be broadcast on television or streamed on any streaming services. So this means that the OVAs can sometimes be more explicit because they do not have to follow traditional television broadcasting guidelines.