Q:

Plot another point on top of swarmplot

I want to plot a "highlighted" point on top of swarmplot like this

The swarmplot don't have the y-axis, so I have no idea how to plot that point. 
import seaborn as sns
sns.set(style="whitegrid")
tips = sns.load_dataset("tips")
ax = sns.swarmplot(x=tips["total_bill"])

A:

This approach is predicated on knowing the index of the data point you wish to highlight, but it should work - although if you have multiple swarmplots on a single Axes instance it will become slightly more complex. 
import matplotlib.pyplot as plt
import matplotlib
import seaborn as sns
sns.set(style="whitegrid")
tips = sns.load_dataset("tips")
ax = sns.swarmplot(x=tips["total_bill"])
artists = ax.get_children()
offsets = []
for a in artists:
    if type(a) is matplotlib.collections. PathCollection:
        offsets = a.get_offsets()
        break
plt.scatter(offsets[50,0], offsets[50,1], marker='o', color='orange', zorder=10)

