Intrusive (adjective)

1. Tending to intrude or interfere with privacy or personal affairs.
2. Tending to encroach upon another's territory or property.
3. Tending to insert or thrust oneself into a situation.

Origin:

Late latin intrusus, past participle of intromittere to insert, from latin in- + tendere to stretch.

Examples:

1. The intrusive reporter wouldn't leave the celebrity alone.
2. The intrusive software was slowing down the computer.
3. The intrusive advertisement was annoying the users.
4. The intrusive questions made the interviewee uncomfortable.
5. The intrusive behavior was not appropriate for the occasion.