<div class="container">
  <div class="message-bubble">
    <p>Some message here and so on lorem ipsum dolor shit ...</p>
  </div>
</div>

body {
  margin: 0;
  height: 100vh;
}

.container {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.message-bubble {
  background: lightgrey;
  text-align: center;
  height: 120px;
  width: 200px;
  padding: 12px;
  box-sizing: border-box;
  display: flex;
  align-items: center;
  border-radius: 10px;
  border-bottom-right-radius: 0;
  position: relative;
}

.message-bubble:after {
  content: ' ';
  position: absolute;
  width: 0;
height: 0;
border-style: solid;
border-width: 30px 0 0 30px;
border-color: transparent transparent transparent lightgrey;
  bottom: 0;
  right: -20px;
}