How to make a fixed block in bootstrap 4?

Question

css

Guys, please help to make a fixed block in the grid that will work like in this design - fixing only in places where the content in the block ends.

<div class="container">
  <div class="row">
    <div class="col-sm-10">Контент</div>
    <div class="col-sm-2">Фиксированный блок</div>
  </div>
</div>