JSFiddle - React, Tailwind, and code Playground

HTML

<div>
<span>4</span>
<img src="http://dl.hiapphere.com/data/icon/201409/HiAppHere_com_kov.theme.lumos.png" />
</div>

or

<div class="icon">
<img src="http://dl.hiapphere.com/data/icon/201409/HiAppHere_com_kov.theme.lumos.png" />
</div>

CSS

div
{
  position: relative;
  width: 300px;
  height: 300px;
}

span
{
  position: absolute;
  background: red;
  color: white;
  height: 60px;
  width: 60px;
  text-align: center;
  font-family: Tahoma, sans-serif;
  font-size: 40px;
  line-height: 55px;
  border-radius: 10px;
  bottom: 0;
  right: 0;
}

.icon
{
  position: relative;
}
.icon:after
{
  content:"4";
  position: absolute;
  display: block;
  background: red;
  color: white;
  height: 60px;
  width: 60px;
  text-align: center;
  font-family: Tahoma, sans-serif;
  font-size: 40px;
  line-height: 55px;
  border-radius: 10px;
  bottom: 0;
  right: 0;
}