To be fair, most if not all harem leads have an element of density in them; it's just that for Ichika's case it's more apparent because there is nothing else to focus and distract us from it being so
obvious
For anyone curious to know, the densest element in the periodic table is
Osmium, which is twice as dense as Lead
The densest place in the solar system, is the core of the Sun, which is ten times as dense as Lead.
Where Ichika stands on this graph is up to one's own interpretation