index.html

<div class="parent">
    <p>テキストテキスト<br>
        テキストテキスト
    </p>
</div>

style.css

.parent{
    position: relative;
    display: inlinde-block;
}
.parent::before {
    position: absolute;
    left: -1em;
    top: 0;
    content: '';
    width: 2px;
    height: 100%;
    background-color: #000;
    border-radius: 3px;
    fransform: rotare(-30deg);
}
.parent::after {
    position: absolute;
    right: -1em;
    top: 0;
    content: '';
    width: 2px;
    height: 100%;
    background-color: #000;
    border-radius: 3px;
    fransform: rotare(30deg);
}