VictoriaMetrics is a time-series database and query engine mostly used for monitoring data. It can be seen as a Prometheus alternative that is easier to install and manage, and has better performance.
It also has a basic graph viewer / dashboard system to plot the results of queries. This means for very simple use cases, especially when getting started, VictoriaMetrics can replace Grafana as well.
Relation to ClickHouse
The people behind VictoriaMetrics have been early ClickHouse users. There is a really interesting presentation from Aliaksandr Valialkin about the road to VictoriaMetrics and their initial workflow using ClickHouse.
Here are the slides: How ClickHouse Inspired Us to Build a High Performance Time Series Database.